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THE HANDBOOK OF THE BRITISH ASTRONOMICAL ASSOCIATION 2018 2017 October ISSN 0068–130–X
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Page 1: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

THE HANDBOOKOF THE

BRITISH ASTRONOMICALASSOCIATION

2018

2017 October ISSN 0068–130–X

Page 2: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

CONTENTSPREFACE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2HIGHLIGHTS FOR 2018 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3SKY DIARY . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5CALENDAR 2018 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6SUN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9ECLIPSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-15APPEARANCE OF PLANETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16VISIBILITY OF PLANETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17RISING AND SETTING OF THE PLANETS IN LATITUDES 52°N AND 35°S . . . . . . . . . . . . 18-19PLANETS – Explanatin of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20ELEMENTS OF PLANETARY ORBITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21MERCURY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22-23VENUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24EARTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25MOON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

LUNAR LIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26MOONRISE AND MOONSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27-31SUN’S SELENOGRAPHIC COLONGITUDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32LUNAR OCCULTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33-39GRAZING LUNAR OCCULTATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40-41

MARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42-43ASTEROIDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

ASTEROID EPHEMERIDES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45-49ASTEROID OCCULTATIONS (incl. TNO Hightlight:1998 WV31) . . . . . . . . . . . . . . . . . . . . 50-53ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES . . . . . . . . . . . . . . . . . . . . . . . 54-56NEO CLOSE APPROACHES TO EARTH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

JUPITER . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58-62SATELLITES OF JUPITER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 62-66JUPITER ECLIPSES, OCCULTATIONS AND TRANSITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67-76

SATURN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77-80SATELLITES OF SATURN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81-84

URANUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85NEPTUNE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86TRANS–NEPTUNIAN & SCATTERED-DISK OBJECTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87DWARF PLANETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88-91COMETS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92-96METEOR DIARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97-99VARIABLE STARS (RZ Cassiopeiae; Algol; RS Canum Venaticorum) . . . . . . . . . . . . . . . . . . 100-101MIRA STARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102VARIABLE STAR OF THE YEAR (VV Cephei) . . . . . .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . 103-105EPHEMERIDES OF VISUAL BINARY STARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106-107BRIGHT STARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108ACTIVE GALAXIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109TIME . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110-111ASTRONOMICAL AND PHYSICAL CONSTANTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112-113INTERNET RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114-115GREEK ALPHABET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115ACKNOWLEDGEMENTS / ERRATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116 Front Cover: Mars - Apparent Diam. 18.4" taken from Barbados on 2016 June 05 by Damian Peach using a 356mm aper-ture Schmidt-Cassegrain telescope (North up)

Page 3: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

British Astronomical Association

HANDBOOK FOR 2018NINETY–SEVENTH YEAR OF PUBLICATION

BURLINGTON HOUSE, PICCADILLY, LONDON, W1J 0DUTelephone 020 7734 4145

Page 4: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

2 Preface BAA Handbook 2018

PREFACE

Welcome to the 97th Handbook of the British Astronomical Association.

The Handbook tries to highlight forthcoming astronomical events for the year but there are always events that can be missed, or are entirely unpredictable, like comets, asteroid close approaches, aurorae, etc. Make sure you watch the BAA’s website for the latest news. Also, make sure you are receiving the new email newsletters by keeping your email up to date with the BAA office.

Once again we would also encourage everyone to join their local astronomical society to try equipment, talk to like-minded people, and to give and receive help. It can take a long time to choose the right equipment and learn how to use it, so make the most of your local society. The BAA’s Sections can help too. Contact the Section Directors, who will be pleased to help.

Don't forget the special BAA Summer Meeting & Joint BAAVSS-AAVSO Meeting to be held at Warwick University : Saturday-Sunday July 7-8 (Organisers: Hazel Collett & Roger Pickard). (https://britastro.org/node/10727)

You may also like to consider getting involved with the annual events organised as part of World Space Week (4-10 Oct.). This is an international celebration of all things SPACE and focuses on science and technology and its role in the past, present and future of mankind. World Space Week currently consists of space education and outreach events held by space agencies, aerospace companies, schools, planetaria, museums, and astronomy clubs around the world. (http://www.worldspaceweek.org/).

Unfortunately we are restricted by the number of pages that we can include in the Handbook. This does mean that some things will have to be left out. However, the Computing Section does try to publish all additional data on the section website (http://britastro.org/computing). Members may also like to know that the Computing Section provides the data for the Royal Astronomical Society’s Diary.

Finally, we must thank all the contributors to the Handbook. You will find them acknowledged on page 116. Contact details for many of these can be found at the back of every Journal. Alternatively, email the Director, Steve Harvey (address below) and messages can be forwarded to those concerned.

Clear skies for 2018 !

Steve HarveyDirector, Computing SectionEmail: [email protected]

August 2017

Page 5: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

BAA Handbook 2018 Highlights 3

HIGHLIGHTS FOR 2018The following events during 2018 are worthy of note:Sun and Moon:There will be five eclipses (three of the Sun and two of the Moon). All three solar eclipses are partial and in polar regions so will be difficult to observe, The two lunar eclipse are both full. The eclipse of July 27 will be the most central umbral shadow since 2011. It will be visible (having already started) from moonrise in the UK.

Planets, Dwarf Planets and Asteroids:Mercury is best seen in northern latitudes in the mornings in early January and mid to late August (for southern latitudes it is best seen in early to mid-January and mid-April to mid-May. In the evenings it is best seen around March and mid-June to early July.(July and late October to mid-November for southern latitudes). Venus is an evening object throughout the middle months of the year, reaching inferior conjunction on 26 Oct.., and then a morning object at the end of the year. A favourable Conjunction occurs with Mars and Jupiter (7 Jan.). Mars rises from the early morning hours at the beginning of the year and is visible throughout the year.Mars reaches perihelic opposition Jul. 27 (05:14) , with a diameter of 24.3" and magnitude -2.8 (From Greenwich transit is at 00:14 13°S)

Meteors:Among the meteor showers, the most favourable are: the Lyrids (April), Perseids (August) and Draconids(October). Also favourable are: Capricornids, ι-Aquarids, Taurids, Leonids and Geminids.

Comets:The comets 21P/Giacobini-Zinner and 46P/Wirtanen, which may reach naked eye brightness. 46P/Wirtanen is a special target for Pro-am observations in 2018. Also worth note (due to its tendency to outburst) is 29P/Schwassmann-Wachmann.Refer to the BAA Comet Section for latest info : http://britastro.org/comet

Space Probes and Artificial Satellites:NASA will launch its first mission to the sun during the summer of 2018 - the Parker Solar Probe.The Juno probe will deorbit into Jupiter during February. ESA's mission to Mercury, BepiColombo is sched-uled for launch in October. Predictions for the International Space Station and other bright satellites can be found for any geographic location at: http://www.heavens-above.com

Highlights by date: Jan. 7 Mars 0.2° South of Jupiter 31 Total lunar eclipse visible from north-west America, the Pacific, Asia and Australia Feb. 15 Partial solar eclipse visible over Antarctica and finishing in South America. Mar. 20 The vernal equinox occurs in the northern hemisphere at 16:16 UT Apr. 22 Lyrid meteor shower May 9 Jupiter at opposition Jun. 28 Saturn at opposition Jun. 21 The summer solstice occurs in the northern hemisphere at 10:08 UT Jul. 13 Partial solar eclipse visible over Antarctica 27 Mars at perihelic opposition 27 Total lunar eclipse visible over Western Africa, and Central Asia, seen rising over South America, Eastern Africa, and Europe Aug. 11 Partial solar eclipse is visible across the Arctic, north-east Canada, north-east Asia at sunrise. 13 Perseid meteor shower Aug. 28 OSIRIS-REx spacecraft will arrive at the asteroid Bennu Sep. 7 Neptune at opposition 23 The autumnal equinox occurs in the northern hemisphere at 01:55 UT Oct. 24 Uranus at opposition Nov. 17 Leonids meteor shower Dec. 14 Geminids meteor shower 21 The winter solstice occurs in the northern hemisphere at 22:23 UT

Page 6: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

4 Sky Diary BAA Handbook 2018

SKY DIARY m d h Phenomenon m d h Lunation 1 1 20 Mercury greatest elongation W(23°) 1 2 02 Full Moon 1 3 21 Quadrantids 1 7 04 Mars 0.2° South of Jupiter 1 8 22 Last Quarter 1 9 07 Venus superior conjunction 1 9 10 Pluto conjunction Sun 1 12 04 Vesta 0.4° North of the Moon 1 13 07 Mercury 0.6° South of Saturn 1 16 11 Pluto 1.8° South of the Moon 1 17 02 New Moon 1 20 20 Neptune 1.6° North of the Moon 1 24 22 First Quarter 1 31 13 Ceres opposition 1 31 13 Total Lunar eclipse 1 31 13 Full Moon

2 7 16 Last Quarter 2 9 13 Vesta 0.9° North of the Moon 2 12 19 Pluto 2° South of the Moon 2 14 11 Juno conjunction Sun 2 15 21 Partial Solar eclipse 2 15 21 New Moon 2 15 18 Mercury 1° South of the Moon 2 16 16 Venus 0.5° North of the Moon 2 17 12 Mercury superior conjunction 2 17 03 Neptune 1.7° North of the Moon 2 21 00 Venus 0.6° South of Neptune 2 23 08 First Quarter 2 25 00 Mercury 0.5° South of Neptune

3 2 01 Full Moon 3 4 14 Neptune conjunction Sun 3 5 00 Mercury 1.4° North of Venus 3 9 19 Vesta 1.7° North of the Moon 3 9 11 Last Quarter 3 12 05 Pluto 1.7° South of the Moon 3 15 15 Mercury greatest elongation E(18°) 3 16 12 Neptune 1.7° North of the Moon 3 17 13 New Moon 3 24 16 First Quarter 3 29 00 Venus 0.07° South of Uranus 3 31 13 Full Moon

4 1 18 Mercury inferior conjunction 4 2 00 Mars 1.2° South of Saturn 4 7 13 Saturn 2° South of the Moon 4 8 07 Last Quarter 4 8 13 Pluto 1.5° South of the Moon 4 12 23 Neptune 2° North of the Moon 4 16 02 New Moon 4 18 14 Uranus conjunction Sun 4 22 - Lyrids 4 22 22 First Quarter 4 29 18 Mercury greatest elongation W(27°) 4 30 01 Full Moon

5 4 20 Saturn 1.7° South of the Moon 5 5 - Eta Aquarids 5 5 21 Pluto 1.3° South of the Moon 5 8 02 Last Quarter 5 9 00 Jupiter opposition 5 15 12 New Moon 5 22 04 First Quarter 5 29 14 Full Moon 5 31 15 Vesta 2° North of the Moon

6 1 01 Saturn 1.6° South of the Moon 6 2 04 Pluto 1.2° South of the Moon 6 6 02 Mercury superior conjunction 6 6 19 Last Quarter 6 13 20 New Moon 6 19 20 Vesta opposition 6 20 11 First Quarter 6 27 13 Saturn opposition 6 27 09 Vesta 0.2° South of the Moon 6 28 03 Saturn 1.8° South of the Moon 6 28 05 Full Moon 6 29 09 Pluto 1.2° South of the Moon

Page 7: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

BAA Handbook 2018 Sky Diary 5

SKY DIARYcont'd m d h Phenomenon m d h Lunation 7 6 08 Last Quarter 7 12 05 Mercury greatest elongation E(26°) 7 12 10 Pluto opposition 7 13 03 Partial Solar eclipse 7 13 03 New Moon 7 16 03 Venus 1.6° South of the Moon 7 19 20 First Quarter 7 25 05 Saturn 2° South of the Moon 7 26 14 Pluto 1.3° South of the Moon 7 27 05 Mars opposition 7 27 20 Total Lunar Eclipse 7 27 20 Full Moon 7 29 - Delta Aquarids 8 4 18 Last Quarter

8 9 02 Mercury inferior conjunction 8 11 10 Partial Solar eclipse 8 11 10 New Moon 8 13 01 Perseids 8 17 17 Venus greatest elongation E(46°) 8 18 08 First Quarter 8 22 19 Pluto 1.4° South of the Moon 8 26 12 Full Moon 8 26 20 Mercury greatest elongation W(18°) 9 3 03 Last Quarter

9 7 18 Neptune opposition 9 8 22 Mercury 2° South of the Moon 9 9 18 New Moon 9 16 23 First Quarter 9 21 01 Mercury superior conjunction 9 25 03 Full Moon

10 2 10 Last Quarter 10 7 10 Ceres conjunction Sun 10 9 04 New Moon 10 15 02 Saturn 1.8° South of the Moon 10 16 09 Pluto 1° South of the Moon 10 16 18 First Quarter 10 18 13 Mars 2° South of the Moon 10 21 - Orionids 10 24 00 Uranus opposition 10 26 14 Venus inferior conjunction 10 24 17 Full Moon 10 31 17 Last Quarter

11 5 - Taurids 11 6 15 Mercury greatest elongation E(23°) 11 7 16 New Moon 11 11 16 Saturn 1.4° South of the Moon 11 12 18 Pluto 1° South of the Moon 11 15 15 First Quarter 11 16 04 Mars 1° North of the Moon 11 18 01 Leonids 11 23 06 Full Moon 11 26 06 Jupiter conjunction Sun 11 27 09 Mercury inferior conjunction 11 28 00 Mercury 0.4° North of Jupiter 11 30 00 Last Quarter

12 5 21 Mercury 2° South of the Moon 12 7 07 New Moon 12 7 15 Mars 0.04° North of Neptune 12 9 05 Saturn 1° South of the Moon 12 10 03 Pluto 0.7° South of the Moon 12 14 08 Geminids 12 15 11 Mercury greatest elongation W(22°) 12 15 12 First Quarter 12 21 15 Mercury 0.8° North of Jupiter 12 22 - Ursids 12 22 18 Full Moon 12 29 10 Last Quarter

Page 8: The British Astronomical Association Handbook 2018 · Welcome to the 97th Handbook of the British Astronomical Association. The Handbook tries to highlight forthcoming astronomical

6 BAA Handbook 2018

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BAA Handbook 2018 Sun 7

SUNThe tables on p.8–9 give the apparent RA, Dec. and diameter of the Sun, the UT of transit across the Greenwich meridian, and P, B0, L0 where

P is the position angle of the N end of the axis of rotation. It is positive when east of the north point of the disk, negative if west; B0 is the heliographic latitude of the centre of the disk; L0 is the heliographic longitude of the centre of the disk.

Decrease of L0 with Time h m º h m º h m º h m º h º

0 00 0.0 1 43 1.0 3 32 2.0 5 21 3.0 6 3.3 05 0.1 54 1.1 43 2.1 32 3.1 8 4.4 16 0.2 2 05 1.2 54 2.2 43 3.2 10 5.5 27 0.3 16 1.3 4 05 2.3 54 3.3 12 6.6 38 0.4 27 1.4 16 2.4 6 05 3.4 14 7.7 49 0.5 38 1.5 27 2.5 16 3.5 16 8.8 1 00 0.6 49 1.6 38 2.6 27 3.6 18 9.9 10 0.7 3 00 1.7 49 2.7 38 3.7 20 11.0 21 0.8 10 l.8 5 00 2.8 49 3.8 22 12.1 32 0.9 21 1.9 10 2.9 7 00 3.9 24 13.2 43 1.0 32 2.0 21 3.0 10 4.0

The heliographic longitude and latitude of a spot may be conveniently estimated by the method described in J. Br. Astron. Assoc., 53, 63 (1943).

Carrington Rotation NumberThe dates of commencement of the synodic rotations, in continuation of Carrington’s (Greenwich Photo–Heliographic) series, are as follows: Rotation Begins Rotation Begins Rotation Begins d d d 2200 Jan. 27.27 2201 Feb. 23.61 2202 Mar. 22.93 2203 Apr. 19.21 2204 May 16.45 2205 Jun. 12.65 2206 Jul. 9.85 2207 Aug. 6.06 2208 Sep. 2.30 2209 Sep. 29.57 2210 Oct. 26.86 2211 Nov. 23.16 2212 Dec. 20.49

At the date of commencement of each synodic rotation period the value of L0 is zero; that is, the prime meridian passes through the central point of the disk.The sidereal period of rotation of the Sun used in physical ephemerides is 25.38 mean solar days, after Carrington; the mean synodic rotation period is 27.2753d

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8 Sun BAA Handbook 2018

SUN

2017/8 RA Dec. Diam. Transit P B0 L0 h m ° ' ' " h m ° ° °Dec 29 18 32.4 –23 14 32 32 12 02 3.54 –2.65 25.49

Jan 3 18 54.5 –22 51 32 32 12 05 1.12 –3.23 319.63 8 19 16.5 –22 16 32 32 12 07 –1.30 –3.80 253.79 13 19 38.2 –21 31 32 31 12 09 –3.69 –4.33 187.94 18 19 59.7 –20 36 32 31 12 10 –6.02 –4.83 122.11 23 20 20.8 –19 30 32 30 12 12 –8.29 –5.29 56.27 28 20 41.7 –18 16 32 29 12 13 –10.46 –5.71 350.44

Feb 2 21 2.2 –16 53 32 28 12 14 –12.54 –6.08 284.61 7 21 22.3 –15 23 32 26 12 14 –14.49 –6.41 218.77 12 21 42.2 –13 47 32 24 12 14 –16.32 –6.68 152.94 17 22 1.7 –12 05 32 22 12 14 –18.02 –6.90 87.10 22 22 20.9 –10 18 32 20 12 13 –19.57 –7.07 21.26 27 22 39.9 –8 27 32 18 12 13 –20.97 –7.19 315.40

Mar 4 22 58.6 –6 33 32 16 12 12 –22.22 –7.24 249.54 9 23 17.2 –4 36 32 13 12 10 –23.30 –7.24 183.66 14 23 35.6 –2 38 32 11 12 09 –24.23 –7.19 117.77 19 23 53.9 –0 40 32 08 12 08 –24.98 –7.08 51.87 24 0 12.1 +1 19 32 05 12 06 –25.57 –6.92 345.95 29 0 30.3 +3 16 32 03 12 05 –25.98 –6.71 280.01

Apr 3 0 48.5 +5 12 31 60 12 03 –26.21 –6.45 214.05 8 1 6.8 +7 06 31 57 12 02 –26.26 –6.14 148.07 13 1 25.2 +8 57 31 54 12 00 –26.13 –5.78 82.07 18 1 43.7 +10 44 31 52 11 59 –25.82 –5.39 16.05 23 2 2.4 +12 26 31 49 11 58 –25.32 –4.96 310.01 28 2 21.2 +14 04 31 47 11 57 –24.64 –4.49 243.95

May 3 2 40.3 +15 35 31 44 11 57 –23.78 –3.99 177.87 8 2 59.6 +17 01 31 42 11 56 –22.74 –3.47 111.78 13 3 19.1 +18 19 31 40 11 56 –21.52 –2.92 45.66 18 3 38.9 +19 29 31 38 11 56 –20.14 –2.35 339.54 23 3 58.9 +20 31 31 36 11 57 –18.60 –1.77 273.40 28 4 19.1 +21 25 31 34 11 57 –16.91 –1.18 207.24

Jun 2 4 39.6 +22 09 31 33 11 58 –15.09 –0.58 141.08 7 5 0.1 +22 43 31 31 11 59 –13.15 0.03 74.90 12 5 20.8 +23 08 31 30 12 00 –11.10 0.63 8.73 17 5 41.6 +23 22 31 29 12 01 –8.98 1.23 302.54 22 6 2.4 +23 26 31 29 12 02 –6.78 1.82 236.36 27 6 23.2 +23 20 31 28 12 03 –4.55 2.39 170.18

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BAA Handbook 2018 Sun 9

SUN

2018 RA Dec. Diam. Transit P B0 L0 h m ° ' ' " h m ° ° °Jul 2 6 43.9 +23 03 31 28 12 04 –2.29 2.95 103.99 7 7 4.5 +22 36 31 28 12 05 –0.02 3.49 37.81 12 7 24.9 +21 60 31 28 12 06 2.23 4.01 331.64 17 7 45.2 +21 14 31 28 12 06 4.45 4.50 265.48 22 8 5.2 +20 19 31 29 12 06 6.62 4.95 199.32 27 8 25.0 +19 16 31 30 12 07 8.73 5.38 133.18

Aug 1 8 44.6 +18 05 31 31 12 06 10.76 5.77 67.04 6 9 3.9 +16 46 31 32 12 06 12.70 6.11 0.92 11 9 22.9 +15 20 31 34 12 05 14.55 6.42 294.81 16 9 41.7 +13 49 31 35 12 04 16.28 6.68 228.71 21 10 0.3 +12 12 31 37 12 03 17.90 6.89 162.63 26 10 18.7 +10 30 31 39 12 02 19.40 7.06 96.56 31 10 37.0 +8 44 31 41 12 00 20.76 7.17 30.50

Sep 5 10 55.1 +6 54 31 43 11 59 21.99 7.24 324.45 10 11 13.1 +5 02 31 46 11 57 23.08 7.25 258.42 15 11 31.0 +3 08 31 48 11 55 24.01 7.21 192.41 20 11 49.0 +1 12 31 51 11 53 24.80 7.12 126.40 25 12 6.9 –0 45 31 54 11 52 25.42 6.98 60.40 30 12 24.9 –2 42 31 56 11 50 25.87 6.78 354.42

Oct 5 12 43.0 –4 38 31 59 11 48 26.16 6.53 288.44 10 13 1.3 –6 32 32 02 11 47 26.26 6.24 222.47 15 13 19.8 –8 25 32 04 11 46 26.19 5.89 156.52 20 13 38.5 –10 14 32 07 11 45 25.92 5.51 90.56 25 13 57.5 –12 00 32 10 11 44 25.47 5.08 24.62 30 14 16.7 –13 41 32 13 11 44 24.82 4.61 318.68

Nov 4 14 36.3 –15 17 32 15 11 44 23.97 4.10 252.75 9 14 56.2 –16 47 32 17 11 44 22.93 3.56 186.82 14 15 16.5 –18 09 32 20 11 44 21.69 3.00 120.91 19 15 37.2 –19 24 32 22 11 45 20.27 2.41 54.99 24 15 58.1 –20 29 32 24 11 47 18.66 1.80 349.08 29 16 19.4 –21 26 32 26 11 48 16.89 1.17 283.18

Dec 4 16 41.0 –22 12 32 27 11 50 14.96 0.54 217.29 9 17 2.8 –22 47 32 29 11 52 12.89 –0.10 151.40 14 17 24.8 –23 11 32 30 11 55 10.70 –0.75 85.52 19 17 47.0 –23 24 32 31 11 57 8.41 –1.38 19.65 24 18 9.2 –23 25 32 31 12 00 6.06 –2.00 313.78 29 18 31.3 –23 14 32 32 12 02 3.66 –2.61 247.92

Jan 3 18 53.4 –22 52 32 32 12 04 1.23 –3.20 182.07

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10 Eclipses BAA Handbook 2018

ECLIPSES

During 2018 there will be three eclipses of the Sun and two of the Moon.

1. A total eclipse of the Moon on January 31 will be visible over north-western North America, the Pacific, Asia, and Australia.

2. A partial eclipse of the Sun on February 15 starts over Antarctica and ends in Southern Chile and Argentina. (40% eclipsed at best over southernmost South American landfall).

3. A partial eclipse of the Sun on July 13 is visible from Antarctica and a small slither of southern Australia.

4. A total eclipse of the Moon on July 27 is visible over Western Africa, and Central Asia, seen rising over South America, Eastern Africa, and Europe, and setting over Eastern Asia, and Australia. The latter part of the eclipse will only be visible at moonrise from the UK. This eclipse is a fairly central eclipse insofar as it has a gamma value of 0.11 (where 0 is perfectly central and 1.00 is the limit of the earth's umbral shadow). Typically more centrally placed eclipses produces a deeper red hue at greatest eclipse.This will be the first central lunar eclipse since the June 15, 2011 lunar eclipse.

5. A partial eclipse of the Sun on August 11 is visible across the Arctic, North Eastern Canada, North Eastern Asia at sunrise.

Solar Eclipse Mailing ListThe solar eclipse community is very active and there is a plethora of websites devoted entirely to the subject. To keep up to date join the Solar Eclipse mailing list:

http://groups.yahoo.com/group/SEML/Useful eclipse websites include:For weather predictions : Jay Anderson's site: http://eclipsophile.com/For general information : Xavier Jubier's site: http://xjubier.free.fr/en/index_en.html or Fred Espenak's: http://www.mreclipse.com/ & http://astropixels.com/

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BAA Handbook 2018 Eclipses 11

ECLIPSES

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12 Eclipses BAA Handbook 2018

ECLIPSES

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BAA Handbook 2018 Eclipses 13

ECLIPSES

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14 Eclipses BAA Handbook 2018

ECLIPSES

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BAA Handbook 2018 Eclipses 15

ECLIPSES

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16 Appearance of Planets BAA Handbook 2018

APP

EA

RA

NC

E O

F PL

AN

ET

SA

PPE

AR

AN

CE

OF

PLA

NE

TS

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BAA Handbook 2018 Visibility of Planets 17

VISIBILITY OF PLANETSThe diagrams on pp 18–19, drawn for latitudes N 52° and S 35° respectively, show the times for the risings and settings of the Sun and the planets. The beginning and end of astronomical twilight (Sun 18° below horizon) is also shown. The times are in Local Mean Time and are thus in GMT (= UT) for Greenwich.

Since dates change at midnight, the dates at the top differ by one day from those at the foot. Each vertical line, followed upwards, indicates the succession of phenomena in the course of one night.Thus, at latitude N 52° on the night of March 31-April 1, Mercury rises at 5h 35m and Venus sets at 20h 20m, Mars and Saturn rise close to 2h 10m, Jupiter rises at 22h 15m. Uranus sets during twilight at 20h 00m, Neptune rises at 05h 05m. Sunrise is at 05h 35m and sunset at 18h 30m, (Timings derived from diagram to nearest 5 minutes.)

The UT of any phenomenon seen from elsewhere than Greenwich may be obtained as follows:

1. For longitudes east of Greenwich, subtract the longitude, expressed as time. For longitudes west of Greenwich, add the longitude expressed as time. (One degree of longitude represents 4 minutes.) This applies both to rising and to setting times.

2. Correct for latitude using a value for Δh from the table below. Add Δh, for setting times and subtract Δh for rising times. The correction should be obtained by interpolating in both latitude and declination.

Δh TABLE Latitude Dec. Latitude N 58° N 55° N 50° N 40° N 30° N 20° 0° S 20° S 25° S 30° S 40° S 45° m m m m m m ° m m m m m m

+69 +29 –15 –70 –106 –134 29 +91 +45 +31 +17 –20 –43 +62 +26 –14 –66 –100 –127 28 +87 +43 +30 +16 –19 –41 +56 +24 –13 –62 –94 –120 27 +84 +41 +29 +15 –18 –39 +51 +22 –12 –58 –89 –114 26 +80 +39 +27 +14 –17 –37 +46 +20 –12 –54 –84 –107 25 +76 +37 +26 +14 –16 –35 +31 +14 –8 –40 –63 –81 20 +59 +29 +20 +11 –12 –26 +21 +10 –6 –28 –45 –58 15 +43 +21 +15 +8 –9 –19 +13 +6 –4 –18 –29 –37 10 +28 +14 +10 +5 –6 –12 +6 +3 –2 –9 –14 –18 5 +14 +7 +5 +2 –3 –6 0 0 0 0 0 0 0 0 0 0 0 0 0

If Dec. is negative, reverse the sign of Δh.

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18 Visibility of Planets BAA Handbook 2018

RIS

ING

AN

D S

ET

TIN

G O

F PL

AN

ET

S

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BAA Handbook 2018 Visibility of Planets 19

RIS

ING

AN

D S

ET

TIN

G O

F PL

AN

ET

S

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20 Planets BAA Handbook 2018

PLANETSThe ephemerides of all the planets (except the dwarf planets and the minor planets), and also the diagrams for Uranus and Neptune, are referred to the apparent equinox, so that the RA and Dec. required for setting on the telescope are obtained directly from the ephemeris. For the minor planets and comets, astrometric ephemerides referred to the equinox of 2000.0 are given. Thus they are directly comparable with star catalogues and atlases referred to this epoch; however, precession should be applied to their positions before setting on a telescope. The magnitudes given are visual. For the minor planets, it should be noted that photographic magnitudes are fainter by about 0.7.The Sky Diary lists other phenomena in chronological order. Relative positions in the Diary are geocentric. Some headings in the tables are abbreviated, as follows:

a = Length of semi–major axis of orbit auCM = The longitude of central meridian °DE = Planetocentric declination of the Earth (called ‘Tilt’ in previous Handbooks) °DS = Planetocentric declination of the Sun °e = Eccentricity of orbit Elong. = Elongation of the planet from the Sun (where + is east and – is west) °H = Mean absolute asteroid magnitude i = Inclination °LS = The planetocentric longitude of the Sun, measured in the plane of the orbit from its ascending node on the Martian equator and given as a direct and exact indicator of the Martian season. The Martian Vernal Equinox (N. Hemisphere) occurs when LS = 0°. °M = Mean anomaly at the epoch °V = Visual magnitude Node = Longitude of the ascending node °P = Position angle of the axis of rotation, or of an occultation, measured eastwards from the north point of the disk °Peri. = Argument of perihelion °Ph. = Phase, the fraction of the disk area that is illuminated Q = Position angle of the point of greatest defect of illumination. The position angle of the line of cusps is Q±90°. °r = Heliocentric distance auU = Uncertainty codeΔ = Distance from Earth au

λ☉ = Solar longitude °Longitudes of central meridians refer to the geometric disks.

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BAA Handbook 2018 Elements of Planetary Orbits 21

ELEMENTS OF PLANETARY ORBITS

KEPLERIAN ELEMENTS FOR THE EPOCH 2018 JAN. 0.5 TT

Mean Longitude Mean Longitude Mean Longitude Inclination at the of the of the to the Mean Planet Epoch Perihelion Ascending Node Ecliptic Eccentricity Distance L ϖ Ω i e a

º º º º auMercury 157.584 77.736 48.544 7.005 0.20564 0.3871Venus 275.438 131.816 76.842 3.395 0.00676 0.7233Earth 100.605 103.247 - - 0.01670 1Mars 200.938 336.392 49.697 1.850 0.09342 1.5237Jupiter 220.886 14.622 100.648 1.302 0.04853 5.2026Saturn 270.309 93.411 113.823 2.488 0.05549 9.5549Uranus 31.431 173.273 74.100 0.773 0.04638 19.2180Neptune 343.928 48.377 131.982 1.768 0.00946 30.1100

Keplerian elements are referred to the mean ecliptic and adjusted for best fit. The elements can be used for the determination of approximate positions of the planets according to Standish, E.M. and Williams, J.G.:

http://ssd.jpl.nasa.gov/txt/aprx_pos_planets.pdf

Sidereal Mean Mean Perihelion Aphelion Mean Daily Sidereal Synodic Orbital Distance Distance Motion Period Period Velocity q Q n P au au ° d d km/sMercury 0.30750 0.46670 4.09234 87.9681 115.88 47.87Venus 0.71844 0.72822 1.60214 224.697 583.91 35.02Earth 0.9833 1.0167 0.98561 365.253 n/a 29.78Mars 1.3813 1.6660 0.52404 686.963 779.94 24.13Jupiter 4.9501 5.4551 0.08306 4334.35 398.87 13.06Saturn 9.0247 10.085 0.03337 10787.8 378.05 9.64Uranus 18.327 20.110 0.01170 30773.0 369.64 6.79Neptune 29.826 30.395 0.00597 60348.7 367.48 5.43

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22 Mercury BAA Handbook 2018

MERCURYMorning Apparition

Greatest Elongation W Superior Conjunction Jan. 1 (23°) Feb. 17 Apr. 29 (27°) Jun. 6 Aug. 26 (18°) Sep. 21 Dec. 15 (21°) When best seen: Northern Hemisphere: early Jan., mid to late Aug. Southern Hemisphere: early to mid Jan., mid Apr.to mid May

2018 RA Dec V Diam Ph. Elong. CM Δh m ° ' " ° ° au

Jan. –3 16 54.9 –20 03 –0.1 7.3 0.501 –22 278 0.9132 17 12.6 –21 07 –0.3 6.6 0.642 –23 305 1.0197 17 36.7 –22 11 –0.3 6.0 0.740 –22 330 1.113

12 18 4.6 –23 01 –0.3 5.6 0.809 –21 354 1.19417 18 34.9 –23 26 –0.3 5.3 0.860 –19 18 1.26022 19 6.8 –23 23 –0.4 5.1 0.898 –17 41 1.31327 19 39.6 –22 48 –0.4 4.9 0.928 –14 64 1.354

Feb. 1 20 13.2 –21 40 –0.6 4.8 0.952 –11 87 1.3826 20 47.2 –19 57 –0.8 4.8 0.973 –8 109 1.399

11 21 21.5 –17 39 –1.1 4.8 0.988 –5 132 1.40216 21 56.0 –14 45 –1.5 4.8 0.997 –1 153 1.391

Apr. 2 0 38.8 +7 13 5.3 11.2 0.004 0 24 0.5957 0 26.1 +4 36 3.6 11.3 0.038 –9 58 0.590

12 0 19.0 +2 22 2.2 10.8 0.118 –17 92 0.61717 0 19.5 +1 04 1.4 10.0 0.213 –22 123 0.66522 0 27.2 +0 51 0.9 9.2 0.306 –25 152 0.72827 0 40.7 +1 36 0.6 8.4 0.393 –27 179 0.798

May 2 0 59.0 +3 08 0.4 7.6 0.473 –27 205 0.8747 1 21.2 +5 19 0.2 7.0 0.551 –26 230 0.954

12 1 47.0 +8 01 –0.1 6.5 0.630 –24 254 1.03517 2 16.3 +11 05 –0.3 6.0 0.714 –21 277 1.11522 2 49.5 +14 24 –0.7 5.6 0.804 –17 299 1.19227 3 27.0 +17 45 –1.1 5.3 0.894 –12 320 1.258

Jun. 1 4 9.2 +20 51 –1.7 5.1 0.969 –6 340 1.3056 4 55.2 +23 20 –2.3 5.1 1..000 0 360 1.322

Aug. 10 9 7.1 +11 36 4.7 11.0 0.012 –2 338 0.60915 8 55.6 +13 23 3.1 10.1 0.060 –10 12 0.65920 8 53.3 +14 57 1.4 8.9 0.179 –15 44 0.74825 9 3.4 +15 47 0.2 7.7 0.357 –18 72 0.86730 9 25.3 +15 28 –0.6 6.7 0.565 –18 98 1.002

Sep. 4 9 56.0 +13 52 –1.0 5.9 0.760 –15 121 1.1349 10 31.0 +11 08 –1.3 5.4 0.898 –11 143 1.244

14 11 6.8 +7 39 –1.5 5.0 0.971 –6 164 1.32419 11 41.3 +3 48 –1.6 4.9 0.997 –2 185 1.374

Nov. 28 16 9.8 –19 54 5.1 9.8 0.003 –1 185 0.680Dec. 3 15 47.9 –17 35 1.6 9.1 0.131 –12 221 0.733

8 15 43.0 –16 55 0.2 8.0 0.354 –18 253 0.83813 15 53.5 –17 43 –0.3 7.0 0.553 –21 281 0.95618 16 13.7 –19 13 –0.4 6.3 0.695 –21 307 1.06823 16 39.5 –20 50 –0.4 5.7 0.791 –20 332 1.16428 17 8.5 –22 16 –0.4 5.4 0.856 –18 355 1.24433 17 39.6 –23 21 –0.4 5.1 0.901 –16 19 1.308

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BAA Handbook 2018 Mercury 23

MERCURYEvening Apparition

Greatest Elongation E Inferior Conjunction Mar. 15 (18°) Apr. 1 Jul. 12 (26°) Aug. 9 Nov. 6 (23°) Nov. 27

When best seen: Northern Hemisphere: Mar., mid Jun. to early Jul. Southern Hemisphere: Jul., Late Oct. to mid Nov.

2018 RA Dec V Diam. Ph. Elong. CM Δh m ° ' " ° ° au

Feb. 21 22 30.7 –11 15 –1.5 4.9 0.994 3 175 1.36026 23 5.2 –7 15 –1.4 5.1 0.966 7 196 1.307

Mar. 3 23 38.8 –2 52 –1.3 5.5 0.893 12 217 1.2258 0 9.9 +1 34 –1.0 6.0 0.756 16 239 1.115

13 0 35.4 +5 31 –0.6 6.8 0.559 18 262 0.982

18 0 52.0 +8 23 0.2 7.9 0.345 18 288 0.84623 0 57.2 +9 41 1.5 9.2 0.162 15 317 0.72628 0 51.4 +9 12 3.4 10.4 0.043 8 349 0.640

Jun. 11 5 42.8 +24 48 –1.7 5.1 0.968 6 19 1.30316 6 28.9 +25 08 –1.1 5.3 0.890 12 40 1.254

21 7 11.3 +24 25 –0.7 5.6 0.793 17 61 1.18526 7 48.8 +22 55 –0.3 6.0 0.698 21 83 1.106

Jul. 1 8 21.0 +20 54 0.0 6.5 0.609 24 106 1.0236 8 48.1 +18 34 0.2 7.1 0.526 25 130 0.941

11 9 9.8 +16 09 0.5 7.8 0.445 26 155 0.861

16 9 25.9 +13 50 0.7 8.5 0.363 26 181 0.78621 9 35.8 +11 51 1.1 9.3 0.276 24 209 0.71826 9 38.5 +10 26 1.6 10.1 0.186 20 238 0.65931 9 33.6 +9 51 2.5 10.8 0.098 15 270 0.616

Aug. 5 9 21.9 +10 17 3.9 11.2 0.032 7 303 0.597

Sep. 24 12 14.2 –0 09 –1.4 4.8 0.996 2 207 1.40029 12 45.5 –4 02 –1.0 4.7 0.983 6 229 1.407

Oct. 4 13 15.7 –7 45 –0.7 4.8 0.963 10 251 1.3999 13 45.0 –11 14 –0.5 4.9 0.938 13 274 1.377

14 14 13.8 –14 26 –0.4 5.0 0.910 15 296 1.343

19 14 42.2 –17 18 –0.3 5.1 0.876 18 320 1.29724 15 10.1 –19 48 –0.2 5.4 0.833 20 343 1.24029 15 37.4 –21 53 –0.2 5.7 0.778 22 7 1.169

Nov. 3 16 3.1 –23 28 –0.2 6.1 0.704 23 32 1.0878 16 25.7 –24 30 –0.2 6.7 0.601 23 57 0.991

13 16 42.0 –24 49 0.0 7.5 0.458 22 84 0.88718 16 47.1 –24 16 0.7 8.5 0.269 18 114 0.78223 16 35.4 –22 35 2.5 9.5 0.076 10 148 0.702

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24 Venus BAA Handbook 2018

VENUSSuperior Conjunction : Jan. 9

Greatest elongation E : Aug. 17 (46°) Inferior Conjunction : Oct. 26

2018 RA Dec. V Diam. Ph. Elong. Δh m ° ' " ° au

Jan. –8 17 47.8 –23 32 –3.9 9.8 0.998 –4 1.7042 18 42.7 –23 35 –3.9 9.8 1.000 –2 1.710

12 19 37.2 –22 26 –3.9 9.7 1.000 1 1.71122 20 30.3 –20 08 –3.9 9.8 0.999 3 1.709

Feb. 1 21 21.5 –16 52 –3.9 9.8 0.996 6 1.702

11 22 10.6 –12 49 –3.9 9.9 0.991 8 1.69221 22 57.9 –8 11 –3.9 9.9 0.985 10 1.678

Mar. 3 23 43.9 –3 12 –3.9 10.0 0.977 13 1.65913 0 29.2 +1 56 –3.9 10.2 0.967 15 1.63523 1 14.6 +7 01 –3.9 10.4 0.955 18 1.607

Apr. 2 2 0.7 +11 50 –3.9 10.6 0.940 20 1.57412 2 48.1 +16 11 –3.9 10.9 0.924 22 1.53722 3 37.2 +19 51 –3.9 11.2 0.904 25 1.493

May 2 4 28.0 +22 40 –3.9 11.5 0.883 27 1.44512 5 20.2 +24 26 –3.9 12.0 0.858 30 1.392

22 6 12.9 +25 03 –4.0 12.5 0.831 32 1.334Jun. 1 7 5.3 +24 30 –4.0 13.1 0.802 34 1.271

11 7 56.1 +22 48 –4.0 13.9 0.770 37 1.20421 8 44.8 +20 07 –4.0 14.7 0.736 39 1.134

Jul. 1 9 30.9 +16 36 –4.1 15.7 0.700 41 1.060

11 10 14.2 +12 26 –4.1 17.0 0.661 42 0.98421 10 55.1 +7 51 –4.1 18.4 0.619 44 0.90631 11 33.6 +3 00 –4.2 20.2 0.575 45 0.826

Aug. 10 12 10.1 –1 55 –4.3 22.3 0.527 46 0.74620 12 44.4 –6 43 –4.3 25.0 0.474 46 0.667

30 13 16.2 –11 15 –4.4 28.4 0.416 45 0.588Sep. 9 13 44.4 –15 19 –4.5 32.6 0.350 44 0.511

19 14 7.2 –18 42 –4.6 38.0 0.275 40 0.43929 14 21.4 –21 05 –4.6 44.7 0.190 35 0.373

Oct. 9 14 23.0 –22 00 –4.5 52.4 0.101 26 0.31919 14 10.3 –20 49 –4.2 59.0 0.028 14 0.28329 13 49.5 –17 28 –4.0 61.2 0.007 –7 0.272

Nov. 8 13 34.0 –13 28 –4.4 57.3 0.053 –19 0.29118 13 32.3 –10 43 –4.6 50.1 0.139 –30 0.333

28 13 44.4 –9 49 –4.7 42.7 0.231 –38 0.391Dec. 8 14 7.0 –10 30 –4.6 36.4 0.315 –43 0.457

18 14 37.0 –12 11 –4.6 31.5 0.387 –45 0.53028 15 12.5 –14 23 –4.5 27.6 0.451 –47 0.604

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BAA Handbook 2018 Earth / Moon 25

EARTH Perihelion Jan. 03d 03h 17m (147,100,176 km, 0.983303941 au) Aphelion Jul. 06d 16h 15m (152,103,776 km, 1.016750939 au) Equinoxes Mar. 20d 16h 16m Sep. 23d 01h 55m Solstices Jun. 21d 10h 08m Dec. 21d 22h 23m

Obliquity 2000 23.43929° 2018 23.43695°

MOON

PHASES OF THE MOON

New Moon First Quarter Full Moon Last Quarter d h m d h m d h m d h mJan 17 02 18 Jan 24 22 22 Jan 2 02 25 Jan 8 22 26Feb 15 21 06 Feb 23 08 10 Jan 31 13 28 Feb 7 15 55Mar 17 13 13 Mar 24 15 36 Mar 2 00 52 Mar 9 11 21Apr 16 01 58 Apr 22 21 47 Mar 31 12 38 Apr 8 07 19May 15 11 49 May 22 03 50 Apr 30 00 59 May 8 02 10Jun 13 19 44 Jun 20 10 52 May 29 14 21 Jun 6 18 33Jul 13 02 49 Jul 19 19 53 Jun 28 04 54 Jul 6 07 52Aug 11 09 59 Aug 18 07 50 Jul 27 20 22 Aug 4 18 19Sep 9 18 03 Sep 16 23 16 Aug 26 11 57 Sep 3 02 39Oct 9 03 48 Oct 16 18 03 Sep 25 02 54 Oct 2 09 47Nov 7 16 03 Nov 15 14 55 Oct 24 16 46 Oct 31 16 41Dec 7 07 22 Dec 15 11 50 Nov 23 05 40 Nov 30 00 20 Dec 22 17 50 Dec 29 09 35

APSIDES

APOGEE PERIGEE Date Diam. Date Diam. Date Diam. Date Diam. d h ' " d h ' " d h ' " d h ' "Jan 15 02 29 01 Jul 27 05 29 33 Jan 1 21 33 55 Jul 13 08 33 13Feb 11 14 29 10 Aug 23 11 29 32 Jan 30 09 33 45 Aug 10 18 33 08Mar 11 09 29 19 Sep 20 00 29 32 Feb 27 14 33 13 Sep 8 01 32 52Apr 8 05 29 26 Oct 17 19 29 28 Mar 26 17 32 37 Oct 5 22 32 30May 6 00 29 30 Nov 14 15 29 22 Apr 20 14 32 20 Oct 31 20 32 27Jun 2 16 29 34 Dec 12 12 29 13 May 17 21 32 37 Nov 26 12 33 00Jun 30 02 29 33 Jun 14 23 32 58 Dec 24 09 33 34

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26 Lunar BAA Handbook 2018

LUNAR LIBRATION

The libration data are given in two forms: as a size and position angle (P); and as the selenographic longitude and latitude of the centre of the disk.The position angle identifies the point on the edge of the disk most displaced towards the centre of the disk from its mean position and is measured from the North point of the disk (NOT the North Pole of the Moon, which usually does not coincide with the North point of the disk) anticlockwise through celestial East, as shown in Fig. 1. In Fig. 1 N, E, S and W are directions in the sky.Selenographic longitude and latitude are analogous to geographic longitude and latitude, with latitudes of +90º and –90º identifying the Moon's North and South Poles, around which the Moon rotates. Positive longitudes are in the Moon's Eastern hemisphere and negative longitudes in the Moon's Western hemisphere, as shown in Fig. 2 for the case of zero libration. For zero libration the selenographic longitude and latitude of the centre of the disk are both 0º.Note that the Eastern hemisphere (positive selenographic longitude) of the Moon in Fig. 2 roughly corresponds to the Western side (in terms of sky direction) of the disk in Fig. 1.

Maximum Minimum Date Size P Sel Lon Sel Lat Date Size P Sel Lon Sel Lat d º º º º d º º º º Jan. 9.30 9.6 251 7.3 –6.3 Jan. 2.84 3.4 331 2.2 2.6 24.71 9.7 27 –7.1 6.7 17.29 2.7 121 –1.9 –1.9 Feb. 6.25 9.5 246 6.9 –6.6 30.99 2.0 331 1.4 1.4 21.21 8.9 22 –5.9 6.7 Feb. 13.81 2.3 118 –1.7 –1.5 Mar. 6.11 8.9 240 5.9 –6.7 27.85 1.0 325 0.8 0.6 20.17 8.2 17 –4.9 6.5 Mar. 13.09 2.1 119 –1.5 –1.5 Apr. 2.66 8.2 235 4.9 –6.6 27.13 1.0 319 0.8 0.5 15.96 8.2 18 –5.2 6.3 Apr. 9.21 2.1 122 –1.5 –1.5 29.80 8.0 234 4.6 –6.5 22.96 1.9 313 1.7 0.9 May 13.11 8.9 23 –6.3 6.2 May 6.37 2.0 124 –1.4 –1.4 26.62 8.4 240 5.3 –6.5 19.64 2.5 320 2.0 1.5 Jun. 9.70 9.7 26 –7.2 6.5 Jun. 2.67 1.7 124 –1.1 –1.2 22.59 9.4 246 6.6 –6.6 15.92 2.1 327 1.5 1.5 Jul. 7.50 10.2 28 –7.6 6.8 30.15 1.1 123 –0.7 –0.8 20.09 10.1 248 7.5 –6.8 Jul. 13.68 1.1 332 0.7 0.8 Aug. 4.25 10.0 27 –7.2 6.9 27.71 0.4 123 –0.3 –0.3 . 16.86 10.2 247 7.6 –6.8 Aug. 10.57 0.1 101 –0.1 0.0 31.66 9.1 24 –6.1 6.8 24.27 0.2 303 0.1 0.2 Sep. 13.63 9.6 244 7.0 –6.6 Sep. 7.34 1.0 152 –0.7 –0.7 27.60 8.3 17 –5.0 6.6 20.64 0.6 295 0.4 0.4 Oct. 11.16 8.8 240 5.9 –6.4 Oct. 4.52 1.2 141 –1.0 –0.7 24.48 8.1 15 –4.7 6.6 17.90 0.8 302 0.5 0.6 Nov. 7.26 8.2 236 5.1 –6.4 31.29 0.3 137 –0.3 –0.2 20.70 8.7 19 –5.6 6.6 Nov. 14.02 0.8 300 0.6 0.6 Dec. 4.06 8.5 238 5.3 –6.6 27.11 0.4 327 0.3 0.3 18.34 9.5 24 –6.7 6.8 Dec. 11.21 0.9 299 0.7 0.6 31.11 9.4 244 6.5 –6.8 24.54 0.1 111 –0.1 0.0

Fig. 1 Fig. 2

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BAA Handbook 2018 Lunar 27

1. For a moonrise, R1, use the previous moonset, S0, and the following moonset, S2. Form

a = –2R1+S0+S2+8m

2. For a moonset, S1, use the previous moonrise, R0, and the following moonrise, R2. Form

a = 2S1–R0–R2+8m

3. Enter the table on the right with argument a and obtain the Moon’s Dec., by mental interpolation, to 0.1º.

4. Enter the table on p.17 with this Dec. and the required latitude to obtain Δh.5. Moonrise for required latitude = R1 – 1.04 Δh. Moonset for required latitude = S1 + 1.04 Δh. The accuracy of the times so derived is ±3m.

The times thus found are for longitude 0º. For other longitudes it is necessary to calculate the times of the previous (fol-lowing) similar phenomenon at the standard latitude if the observer is east (west) of Greenwich and then interpolate them to the observer’s longitude.

These calculations are most conveniently carried out using a spreadsheet or suit-able applet. Observers are referred to the BAA's Computing Section webpage for support in doing these calculations:

http://britastro.org/computing/applets_moonrts.html

On the four following pages are given the times (UT) of moonrise and moonset for longitude 0°, in the standard latitudes of N 52° and S 35°. Observers in most other latitudes can determine approximate times using the following method, where the times of moonrise and moonset are for the standard latitude in the same hemisphere as the observer. The basis of the method is given in J. Br. Astron. Assoc., 86, 416 (1976).

N 52° S 35° a Dec. a h m ° h m

0 00 0 0 00 0 21 1 0 12 0 42 2 0 23 1 03 3 0 35 1 25 4 0 46 1 46 5 0 58 2 07 6 1 10 2 29 7 1 21 2 51 8 1 33 3 13 9 1 45 3 35 10 1 57 3 58 11 2 09 4 20 12 2 21 4 44 13 2 33 5 07 14 2 46 5 31 15 2 58 5 56 16 3 11 6 21 17 3 24 6 46 18 3 37 7 12 19 3 51 7 39 20 4 04 8 07 21 4 18 8 35 22 4 32 9 05 23 4 46 9 36 24 5 01 10 08 25 5 16 10 41 26 5 31 11 16 27 5 47 11 53 28 6 03 12 31 29 6 20samesignas a

oppsignto a

Dec} {

MOONRISE AND MOONSET

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28 Lunar BAA Handbook 2018

MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE N 52º LATITUDE N 52º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Day h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 15:46 07:00 18:13 08:13 17:02 06:41 19:44 06:25 20:56 05:41 22:32 06:08 22:19 06:48 21:56 09:00 21:34 11:32 21:31 12:59 23:55 14:18 00:20 13:45 2 16:51 08:06 19:32 08:46 18:22 07:11 20:56 06:49 22:00 06:12 23:13 07:00 22:46 07:51 22:17 10:08 22:06 12:45 22:28 14:01 —:— 14:48 01:37 14:06 3 18:06 09:01 20:50 09:13 19:39 07:37 22:05 07:14 22:58 06:47 23:47 07:57 23:09 08:56 22:39 11:18 22:47 13:57 23:36 14:55 01:14 15:14 02:53 14:28 4 19:24 09:44 22:04 09:38 20:53 08:01 23:10 07:42 23:50 07:28 ––:–– 08:58 23:30 10:02 23:03 12:30 23:38 15:06 ––:–– 15:39 02:33 15:38 04:07 14:51 5 20:43 10:19 23:16 10:01 22:06 08:25 ––:–– 08:15 ––:–– 08:16 00:16 10:02 23:51 11:10 23:33 13:43 ––:–– 16:07 00:51 16:15 03:51 16:00 05:21 15:16

6 21:59 10:48 ––:–– 10:24 23:15 08:49 00:11 08:52 00:35 09:10 00:41 11:08 ––:–– 12:20 ––:–– 14:58 00:40 16:59 02:11 16:45 05:07 16:23 06:32 15:45 7 23:12 11:13 00:24 10:49 ––:–– 09:16 01:06 09:36 01:12 10:08 01:03 12:16 00:12 13:32 00:09 16:12 01:54 17:41 03:32 17:11 06:23 16:47 07:40 16:19 8 ––:–– 11:36 01:31 11:16 00:21 09:45 01:55 10:26 01:44 11:11 01:25 13:26 00:35 14:46 00:55 17:20 03:14 18:16 04:53 17:34 07:37 17:14 08:42 17:01 9 00:23 11:58 02:34 11:47 01:24 10:19 02:37 11:22 02:12 12:17 01:46 14:38 01:02 16:04 01:52 18:20 04:36 18:45 06:12 17:58 08:48 17:46 09:37 17:49 10 01:31 12:21 03:34 12:22 02:21 10:59 03:12 12:23 02:36 13:25 02:09 15:54 01:35 17:21 03:02 19:08 05:59 19:10 07:29 18:22 09:53 18:24 10:23 18:44

11 02:37 12:46 04:29 13:04 03:13 11:45 03:43 13:28 02:59 14:35 02:35 17:12 02:17 18:35 04:21 19:48 07:20 19:34 08:45 18:48 10:52 19:08 11:01 19:44 12 03:42 13:14 05:19 13:53 03:59 12:37 04:09 14:35 03:21 15:48 03:05 18:31 03:10 19:40 05:44 20:20 08:38 19:58 09:57 19:17 11:43 20:00 11:32 20:47 13 04:44 13:46 06:02 14:48 04:38 13:36 04:33 15:45 03:44 17:03 03:43 19:48 04:16 20:35 07:07 20:47 09:53 20:23 11:05 19:51 12:26 20:56 11:58 21:51 14 05:42 14:24 06:39 15:48 05:12 14:38 04:56 16:57 04:08 18:21 04:31 20:58 05:31 21:18 08:28 21:11 11:06 20:50 12:07 20:32 13:01 21:58 12:21 22:57 15 06:35 15:08 07:11 16:52 05:41 15:45 05:19 18:11 04:37 19:40 05:31 21:57 06:52 21:53 09:46 21:34 12:14 21:21 13:01 21:19 13:30 23:01 12:41 ––:––

16 07:22 15:59 07:39 17:58 06:07 16:53 05:43 19:27 05:11 20:58 06:41 22:45 08:14 22:21 11:01 21:58 13:18 21:57 13:48 22:12 13:54 ––:–– 13:01 00:04 17 08:04 16:56 08:04 19:07 06:31 18:03 06:09 20:44 05:53 22:10 07:57 23:22 09:34 22:46 12:13 22:23 14:16 22:40 14:27 23:11 14:16 00:07 13:20 01:12 18 08:39 17:57 08:27 20:16 06:53 19:15 06:39 22:01 06:46 23:13 09:17 23:53 10:50 23:09 13:22 22:51 15:07 23:29 14:59 ––:–– 14:37 01:14 13:41 02:23 19 09:09 19:01 08:49 21:27 07:16 20:29 07:16 23:14 07:49 ––:–– 10:35 ––:–– 12:04 23:31 14:27 23:23 15:50 ––:–– 15:26 00:13 14:56 02:23 14:05 03:36 20 09:35 20:08 09:12 22:39 07:41 21:43 08:01 ––:–– 09:00 00:05 11:51 00:19 13:16 23:55 15:28 00:01 16:26 00:24 15:50 01:18 15:17 03:34 14:34 04:53

21 09:59 21:16 09:37 23:53 08:08 22:58 08:56 00:21 10:15 00:47 13:04 00:42 14:25 ––:–– 16:22 ––:–– 16:57 01:24 16:12 02:25 15:40 04:47 15:10 06:10 22 10:21 22:25 10:05 ––:–– 08:40 ––:–– 10:00 01:18 11:32 01:20 14:16 01:03 15:32 00:20 17:10 00:45 17:23 02:27 16:32 03:33 16:07 06:03 15:57 07:26 23 10:43 23:36 10:39 01:07 09:18 00:12 11:11 02:05 12:47 01:48 15:26 01:26 16:35 00:49 17:51 01:36 17:46 03:33 16:53 04:44 16:39 07:20 16:56 08:35 24 11:07 ––:–– 11:20 02:20 10:06 01:22 12:26 02:43 14:01 02:12 16:34 01:49 17:34 01:23 18:25 02:33 18:08 04:41 17:15 05:56 17:20 08:37 18:07 09:33 25 11:33 00:49 12:12 03:29 11:03 02:25 13:43 03:14 15:14 02:34 17:40 02:15 18:26 02:03 18:54 03:35 18:28 05:49 17:39 07:09 18:12 09:48 19:25 10:20

26 12:04 02:04 13:14 04:30 12:10 03:19 14:58 03:41 16:25 02:56 18:42 02:46 19:12 02:49 19:19 04:39 18:49 06:59 18:08 08:25 19:14 10:50 20:47 10:57 27 12:41 03:20 14:25 05:23 13:23 04:03 16:13 04:05 17:35 03:19 19:39 03:22 19:50 03:42 19:42 05:45 19:11 08:11 18:43 09:40 20:26 11:41 22:07 11:26 28 13:28 04:35 15:43 06:06 14:40 04:40 17:26 04:28 18:43 03:44 20:29 04:04 20:23 04:41 20:02 06:52 19:37 09:23 19:27 10:52 21:43 12:22 23:26 11:51 29 14:26 05:44 15:58 05:11 18:38 04:51 19:49 04:12 21:13 04:53 20:50 05:43 20:23 08:00 20:07 10:37 20:21 11:58 23:02 12:54 ––:–– 12:13 30 15:35 06:44 17:15 05:37 19:48 05:15 20:50 04:45 21:49 05:48 21:14 06:48 20:44 09:09 20:44 11:50 21:26 12:54 ––:–– 13:21 00:43 12:35

31 16:52 07:33 18:30 06:02 21:44 05:23 21:36 07:53 21:07 10:20 22:38 13:41 01:57 12:57

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BAA Handbook 2018 Lunar 29

MOONRISE AND MOONSET MOONRISE AND MOONSET

LATITUDE N 52º LATITUDE N 52º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Day h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 15:46 07:00 18:13 08:13 17:02 06:41 19:44 06:25 20:56 05:41 22:32 06:08 22:19 06:48 21:56 09:00 21:34 11:32 21:31 12:59 23:55 14:18 00:20 13:45 2 16:51 08:06 19:32 08:46 18:22 07:11 20:56 06:49 22:00 06:12 23:13 07:00 22:46 07:51 22:17 10:08 22:06 12:45 22:28 14:01 —:— 14:48 01:37 14:06 3 18:06 09:01 20:50 09:13 19:39 07:37 22:05 07:14 22:58 06:47 23:47 07:57 23:09 08:56 22:39 11:18 22:47 13:57 23:36 14:55 01:14 15:14 02:53 14:28 4 19:24 09:44 22:04 09:38 20:53 08:01 23:10 07:42 23:50 07:28 ––:–– 08:58 23:30 10:02 23:03 12:30 23:38 15:06 ––:–– 15:39 02:33 15:38 04:07 14:51 5 20:43 10:19 23:16 10:01 22:06 08:25 ––:–– 08:15 ––:–– 08:16 00:16 10:02 23:51 11:10 23:33 13:43 ––:–– 16:07 00:51 16:15 03:51 16:00 05:21 15:16

6 21:59 10:48 ––:–– 10:24 23:15 08:49 00:11 08:52 00:35 09:10 00:41 11:08 ––:–– 12:20 ––:–– 14:58 00:40 16:59 02:11 16:45 05:07 16:23 06:32 15:45 7 23:12 11:13 00:24 10:49 ––:–– 09:16 01:06 09:36 01:12 10:08 01:03 12:16 00:12 13:32 00:09 16:12 01:54 17:41 03:32 17:11 06:23 16:47 07:40 16:19 8 ––:–– 11:36 01:31 11:16 00:21 09:45 01:55 10:26 01:44 11:11 01:25 13:26 00:35 14:46 00:55 17:20 03:14 18:16 04:53 17:34 07:37 17:14 08:42 17:01 9 00:23 11:58 02:34 11:47 01:24 10:19 02:37 11:22 02:12 12:17 01:46 14:38 01:02 16:04 01:52 18:20 04:36 18:45 06:12 17:58 08:48 17:46 09:37 17:49 10 01:31 12:21 03:34 12:22 02:21 10:59 03:12 12:23 02:36 13:25 02:09 15:54 01:35 17:21 03:02 19:08 05:59 19:10 07:29 18:22 09:53 18:24 10:23 18:44

11 02:37 12:46 04:29 13:04 03:13 11:45 03:43 13:28 02:59 14:35 02:35 17:12 02:17 18:35 04:21 19:48 07:20 19:34 08:45 18:48 10:52 19:08 11:01 19:44 12 03:42 13:14 05:19 13:53 03:59 12:37 04:09 14:35 03:21 15:48 03:05 18:31 03:10 19:40 05:44 20:20 08:38 19:58 09:57 19:17 11:43 20:00 11:32 20:47 13 04:44 13:46 06:02 14:48 04:38 13:36 04:33 15:45 03:44 17:03 03:43 19:48 04:16 20:35 07:07 20:47 09:53 20:23 11:05 19:51 12:26 20:56 11:58 21:51 14 05:42 14:24 06:39 15:48 05:12 14:38 04:56 16:57 04:08 18:21 04:31 20:58 05:31 21:18 08:28 21:11 11:06 20:50 12:07 20:32 13:01 21:58 12:21 22:57 15 06:35 15:08 07:11 16:52 05:41 15:45 05:19 18:11 04:37 19:40 05:31 21:57 06:52 21:53 09:46 21:34 12:14 21:21 13:01 21:19 13:30 23:01 12:41 ––:––

16 07:22 15:59 07:39 17:58 06:07 16:53 05:43 19:27 05:11 20:58 06:41 22:45 08:14 22:21 11:01 21:58 13:18 21:57 13:48 22:12 13:54 ––:–– 13:01 00:04 17 08:04 16:56 08:04 19:07 06:31 18:03 06:09 20:44 05:53 22:10 07:57 23:22 09:34 22:46 12:13 22:23 14:16 22:40 14:27 23:11 14:16 00:07 13:20 01:12 18 08:39 17:57 08:27 20:16 06:53 19:15 06:39 22:01 06:46 23:13 09:17 23:53 10:50 23:09 13:22 22:51 15:07 23:29 14:59 ––:–– 14:37 01:14 13:41 02:23 19 09:09 19:01 08:49 21:27 07:16 20:29 07:16 23:14 07:49 ––:–– 10:35 ––:–– 12:04 23:31 14:27 23:23 15:50 ––:–– 15:26 00:13 14:56 02:23 14:05 03:36 20 09:35 20:08 09:12 22:39 07:41 21:43 08:01 ––:–– 09:00 00:05 11:51 00:19 13:16 23:55 15:28 00:01 16:26 00:24 15:50 01:18 15:17 03:34 14:34 04:53

21 09:59 21:16 09:37 23:53 08:08 22:58 08:56 00:21 10:15 00:47 13:04 00:42 14:25 ––:–– 16:22 ––:–– 16:57 01:24 16:12 02:25 15:40 04:47 15:10 06:10 22 10:21 22:25 10:05 ––:–– 08:40 ––:–– 10:00 01:18 11:32 01:20 14:16 01:03 15:32 00:20 17:10 00:45 17:23 02:27 16:32 03:33 16:07 06:03 15:57 07:26 23 10:43 23:36 10:39 01:07 09:18 00:12 11:11 02:05 12:47 01:48 15:26 01:26 16:35 00:49 17:51 01:36 17:46 03:33 16:53 04:44 16:39 07:20 16:56 08:35 24 11:07 ––:–– 11:20 02:20 10:06 01:22 12:26 02:43 14:01 02:12 16:34 01:49 17:34 01:23 18:25 02:33 18:08 04:41 17:15 05:56 17:20 08:37 18:07 09:33 25 11:33 00:49 12:12 03:29 11:03 02:25 13:43 03:14 15:14 02:34 17:40 02:15 18:26 02:03 18:54 03:35 18:28 05:49 17:39 07:09 18:12 09:48 19:25 10:20

26 12:04 02:04 13:14 04:30 12:10 03:19 14:58 03:41 16:25 02:56 18:42 02:46 19:12 02:49 19:19 04:39 18:49 06:59 18:08 08:25 19:14 10:50 20:47 10:57 27 12:41 03:20 14:25 05:23 13:23 04:03 16:13 04:05 17:35 03:19 19:39 03:22 19:50 03:42 19:42 05:45 19:11 08:11 18:43 09:40 20:26 11:41 22:07 11:26 28 13:28 04:35 15:43 06:06 14:40 04:40 17:26 04:28 18:43 03:44 20:29 04:04 20:23 04:41 20:02 06:52 19:37 09:23 19:27 10:52 21:43 12:22 23:26 11:51 29 14:26 05:44 15:58 05:11 18:38 04:51 19:49 04:12 21:13 04:53 20:50 05:43 20:23 08:00 20:07 10:37 20:21 11:58 23:02 12:54 ––:–– 12:13 30 15:35 06:44 17:15 05:37 19:48 05:15 20:50 04:45 21:49 05:48 21:14 06:48 20:44 09:09 20:44 11:50 21:26 12:54 ––:–– 13:21 00:43 12:35

31 16:52 07:33 18:30 06:02 21:44 05:23 21:36 07:53 21:07 10:20 22:38 13:41 01:57 12:57

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30 Lunar BAA Handbook 2018

MOONRISE AND MOONSET MOONRISE AND MOONSET LATITUDE S 35º LATITUDE S 35º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise SetDay h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 18:43 04:07 20:01 06:09 18:33 04:54 18:53 06:56 18:38 07:44 19:30 09:12 20:03 09:19 21:40 09:35 23:33 09:48 ––:–– 09:59 01:16 11:58 01:18 13:08 2 19:45 05:09 20:42 07:18 19:12 06:02 19:28 07:58 19:18 08:41 20:22 09:58 20:58 09:56 22:38 10:06 ––:–– 10:28 00:36 10:54 02:00 13:05 01:53 14:12 3 20:40 06:16 21:19 08:25 19:48 07:08 20:04 08:58 20:01 09:36 21:15 10:40 21:53 10:29 23:37 10:38 00:37 11:13 01:34 11:55 02:39 14:11 02:26 15:15 4 21:28 07:26 21:54 09:29 20:23 08:12 20:43 09:56 20:48 10:28 22:09 11:19 22:50 11:01 ––:–– 11:12 01:40 12:04 02:28 13:00 03:16 15:17 03:00 16:16 5 22:11 08:34 22:28 10:30 20:58 09:14 21:24 10:52 21:38 11:17 23:05 11:55 23:47 11:33 00:39 11:49 02:43 13:02 03:17 14:08 03:51 16:21 03:35 17:18

6 22:48 09:40 23:01 11:29 21:33 10:13 22:09 11:45 22:30 12:01 ––:–– 12:28 ––:–– 12:04 01:43 12:31 03:41 14:07 04:01 15:17 04:25 17:25 04:12 18:18 7 23:23 10:43 23:36 12:27 22:10 11:12 22:56 12:35 23:24 12:42 00:02 13:00 00:46 12:37 02:48 13:20 04:35 15:16 04:40 16:25 05:00 18:28 04:52 19:15 8 23:56 11:44 ––:–– 13:23 22:49 12:08 23:47 13:22 ––:–– 13:20 00:59 13:32 01:48 13:13 03:54 14:16 05:24 16:26 05:17 17:32 05:37 19:30 05:37 20:10 9 ––:–– 12:42 00:13 14:17 23:31 13:02 ––:–– 14:05 00:19 13:55 01:59 14:05 02:53 13:54 04:57 15:19 06:07 17:37 05:53 18:37 06:16 20:29 06:24 21:01 10 00:28 13:39 00:53 15:10 ––:–– 13:53 00:40 14:45 01:16 14:28 03:01 14:41 04:00 14:40 05:56 16:28 06:46 18:45 06:28 19:41 06:58 21:26 07:15 21:46

11 01:02 14:35 01:36 16:00 00:16 14:42 01:35 15:22 02:14 15:01 04:06 15:20 05:08 15:34 06:48 17:40 07:23 19:52 07:05 20:44 07:44 22:19 08:08 22:28 12 01:37 15:30 02:23 16:47 01:05 15:27 02:32 15:57 03:14 15:34 05:14 16:04 06:14 16:36 07:35 18:51 07:59 20:56 07:42 21:44 08:33 23:07 09:02 23:04 13 02:14 16:24 03:13 17:31 01:57 16:09 03:30 16:31 04:17 16:09 06:23 16:55 07:17 17:43 08:16 20:00 08:34 21:59 08:23 22:42 09:25 23:50 09:57 23:38 14 02:55 17:15 04:06 18:12 02:51 16:48 04:30 17:04 05:21 16:47 07:31 17:54 08:12 18:54 08:54 21:07 09:11 22:59 09:07 23:36 10:18 ––:–– 10:52 ––:–– 15 03:40 18:05 05:01 18:50 03:47 17:24 05:31 17:38 06:28 17:29 08:35 18:58 09:01 20:04 09:29 22:11 09:49 23:58 09:53 ––:–– 11:13 00:30 11:48 00:10

16 04:28 18:51 05:57 19:25 04:45 17:59 06:34 18:14 07:36 18:17 09:33 20:06 09:44 21:13 10:04 23:13 10:30 ––:–– 10:43 00:27 12:08 01:05 12:44 00:40 17 05:19 19:34 06:55 19:59 05:44 18:33 07:39 18:54 08:44 19:10 10:24 21:14 10:22 22:19 10:38 ––:–– 11:14 00:53 11:35 01:12 13:04 01:38 13:42 01:10 18 06:12 20:13 07:53 20:32 06:44 19:06 08:46 19:37 09:49 20:10 11:08 22:22 10:57 23:22 11:15 00:12 12:01 01:44 12:29 01:54 14:01 02:10 14:42 01:41 19 07:07 20:50 08:52 21:05 07:45 19:40 09:52 20:26 10:48 21:14 11:47 23:27 11:31 ––:–– 11:53 01:10 12:52 02:32 13:24 02:32 14:59 02:40 15:45 02:15 20 08:03 21:24 09:52 21:40 08:47 20:17 10:56 21:20 11:41 22:20 12:23 ––:–– 12:04 00:23 12:34 02:06 13:44 03:16 14:20 03:06 15:59 03:12 16:51 02:52

21 09:00 21:57 10:54 22:17 09:51 20:57 11:57 22:20 12:27 23:26 12:56 00:30 12:39 01:23 13:19 02:59 14:39 03:56 15:17 03:39 17:02 03:45 17:58 03:35 22 09:58 22:30 11:57 22:57 10:55 21:41 12:53 23:23 13:08 ––:–– 13:29 01:31 13:15 02:21 14:07 03:49 15:34 04:33 16:15 04:10 18:06 04:21 19:05 04:24 23 10:57 23:03 13:02 23:43 12:00 22:30 13:42 ––:–– 13:45 00:31 14:02 02:30 13:54 03:17 14:59 04:36 16:31 05:07 17:14 04:42 19:13 05:01 20:09 05:22 24 11:58 23:38 14:06 ––:–– 13:02 23:26 14:26 00:28 14:20 01:34 14:37 03:29 14:37 04:12 15:52 05:18 17:28 05:39 18:15 05:14 20:19 05:47 21:06 06:26 25 13:01 ––:–– 15:08 00:35 14:01 ––:–– 15:06 01:34 14:53 02:36 15:14 04:26 15:22 05:04 16:47 05:57 18:26 06:11 19:18 05:48 21:23 06:40 21:57 07:35

26 14:06 00:17 16:07 01:34 14:55 00:26 15:42 02:38 15:26 03:36 15:54 05:22 16:12 05:53 17:42 06:33 19:25 06:42 20:23 06:26 22:22 07:39 22:41 08:45 27 15:13 01:00 17:01 02:38 15:43 01:31 16:17 03:41 16:00 04:36 16:38 06:16 17:04 06:38 18:39 07:06 20:26 07:15 21:27 07:08 23:15 08:43 23:20 09:54 28 16:20 01:50 17:49 03:45 16:27 02:37 16:51 04:43 16:36 05:34 17:26 07:08 17:57 07:19 19:35 07:38 21:28 07:49 22:31 07:55 ––:–– 09:50 23:56 11:01 29 17:23 02:47 17:06 03:44 17:25 05:44 17:14 06:32 18:16 07:55 18:52 07:57 20:33 08:09 22:31 08:27 23:31 08:49 00:01 10:57 ––:–– 12:05 30 18:22 03:51 17:43 04:49 18:00 06:45 17:56 07:28 19:09 08:39 19:48 08:31 21:31 08:40 23:34 09:10 ––:–– 09:48 00:42 12:03 00:29 13:08

31 19:15 04:59 18:18 05:54 18:42 08:22 20:44 09:04 22:32 09:13 00:26 10:52 01:03 14:10

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BAA Handbook 2018 Lunar 31

MOONRISE AND MOONSET MOONRISE AND MOONSET LATITUDE S 35º LATITUDE S 35º

January February March April May June July August September October November December Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise Set Rise SetDay h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m h : m

1 18:43 04:07 20:01 06:09 18:33 04:54 18:53 06:56 18:38 07:44 19:30 09:12 20:03 09:19 21:40 09:35 23:33 09:48 ––:–– 09:59 01:16 11:58 01:18 13:08 2 19:45 05:09 20:42 07:18 19:12 06:02 19:28 07:58 19:18 08:41 20:22 09:58 20:58 09:56 22:38 10:06 ––:–– 10:28 00:36 10:54 02:00 13:05 01:53 14:12 3 20:40 06:16 21:19 08:25 19:48 07:08 20:04 08:58 20:01 09:36 21:15 10:40 21:53 10:29 23:37 10:38 00:37 11:13 01:34 11:55 02:39 14:11 02:26 15:15 4 21:28 07:26 21:54 09:29 20:23 08:12 20:43 09:56 20:48 10:28 22:09 11:19 22:50 11:01 ––:–– 11:12 01:40 12:04 02:28 13:00 03:16 15:17 03:00 16:16 5 22:11 08:34 22:28 10:30 20:58 09:14 21:24 10:52 21:38 11:17 23:05 11:55 23:47 11:33 00:39 11:49 02:43 13:02 03:17 14:08 03:51 16:21 03:35 17:18

6 22:48 09:40 23:01 11:29 21:33 10:13 22:09 11:45 22:30 12:01 ––:–– 12:28 ––:–– 12:04 01:43 12:31 03:41 14:07 04:01 15:17 04:25 17:25 04:12 18:18 7 23:23 10:43 23:36 12:27 22:10 11:12 22:56 12:35 23:24 12:42 00:02 13:00 00:46 12:37 02:48 13:20 04:35 15:16 04:40 16:25 05:00 18:28 04:52 19:15 8 23:56 11:44 ––:–– 13:23 22:49 12:08 23:47 13:22 ––:–– 13:20 00:59 13:32 01:48 13:13 03:54 14:16 05:24 16:26 05:17 17:32 05:37 19:30 05:37 20:10 9 ––:–– 12:42 00:13 14:17 23:31 13:02 ––:–– 14:05 00:19 13:55 01:59 14:05 02:53 13:54 04:57 15:19 06:07 17:37 05:53 18:37 06:16 20:29 06:24 21:01 10 00:28 13:39 00:53 15:10 ––:–– 13:53 00:40 14:45 01:16 14:28 03:01 14:41 04:00 14:40 05:56 16:28 06:46 18:45 06:28 19:41 06:58 21:26 07:15 21:46

11 01:02 14:35 01:36 16:00 00:16 14:42 01:35 15:22 02:14 15:01 04:06 15:20 05:08 15:34 06:48 17:40 07:23 19:52 07:05 20:44 07:44 22:19 08:08 22:28 12 01:37 15:30 02:23 16:47 01:05 15:27 02:32 15:57 03:14 15:34 05:14 16:04 06:14 16:36 07:35 18:51 07:59 20:56 07:42 21:44 08:33 23:07 09:02 23:04 13 02:14 16:24 03:13 17:31 01:57 16:09 03:30 16:31 04:17 16:09 06:23 16:55 07:17 17:43 08:16 20:00 08:34 21:59 08:23 22:42 09:25 23:50 09:57 23:38 14 02:55 17:15 04:06 18:12 02:51 16:48 04:30 17:04 05:21 16:47 07:31 17:54 08:12 18:54 08:54 21:07 09:11 22:59 09:07 23:36 10:18 ––:–– 10:52 ––:–– 15 03:40 18:05 05:01 18:50 03:47 17:24 05:31 17:38 06:28 17:29 08:35 18:58 09:01 20:04 09:29 22:11 09:49 23:58 09:53 ––:–– 11:13 00:30 11:48 00:10

16 04:28 18:51 05:57 19:25 04:45 17:59 06:34 18:14 07:36 18:17 09:33 20:06 09:44 21:13 10:04 23:13 10:30 ––:–– 10:43 00:27 12:08 01:05 12:44 00:40 17 05:19 19:34 06:55 19:59 05:44 18:33 07:39 18:54 08:44 19:10 10:24 21:14 10:22 22:19 10:38 ––:–– 11:14 00:53 11:35 01:12 13:04 01:38 13:42 01:10 18 06:12 20:13 07:53 20:32 06:44 19:06 08:46 19:37 09:49 20:10 11:08 22:22 10:57 23:22 11:15 00:12 12:01 01:44 12:29 01:54 14:01 02:10 14:42 01:41 19 07:07 20:50 08:52 21:05 07:45 19:40 09:52 20:26 10:48 21:14 11:47 23:27 11:31 ––:–– 11:53 01:10 12:52 02:32 13:24 02:32 14:59 02:40 15:45 02:15 20 08:03 21:24 09:52 21:40 08:47 20:17 10:56 21:20 11:41 22:20 12:23 ––:–– 12:04 00:23 12:34 02:06 13:44 03:16 14:20 03:06 15:59 03:12 16:51 02:52

21 09:00 21:57 10:54 22:17 09:51 20:57 11:57 22:20 12:27 23:26 12:56 00:30 12:39 01:23 13:19 02:59 14:39 03:56 15:17 03:39 17:02 03:45 17:58 03:35 22 09:58 22:30 11:57 22:57 10:55 21:41 12:53 23:23 13:08 ––:–– 13:29 01:31 13:15 02:21 14:07 03:49 15:34 04:33 16:15 04:10 18:06 04:21 19:05 04:24 23 10:57 23:03 13:02 23:43 12:00 22:30 13:42 ––:–– 13:45 00:31 14:02 02:30 13:54 03:17 14:59 04:36 16:31 05:07 17:14 04:42 19:13 05:01 20:09 05:22 24 11:58 23:38 14:06 ––:–– 13:02 23:26 14:26 00:28 14:20 01:34 14:37 03:29 14:37 04:12 15:52 05:18 17:28 05:39 18:15 05:14 20:19 05:47 21:06 06:26 25 13:01 ––:–– 15:08 00:35 14:01 ––:–– 15:06 01:34 14:53 02:36 15:14 04:26 15:22 05:04 16:47 05:57 18:26 06:11 19:18 05:48 21:23 06:40 21:57 07:35

26 14:06 00:17 16:07 01:34 14:55 00:26 15:42 02:38 15:26 03:36 15:54 05:22 16:12 05:53 17:42 06:33 19:25 06:42 20:23 06:26 22:22 07:39 22:41 08:45 27 15:13 01:00 17:01 02:38 15:43 01:31 16:17 03:41 16:00 04:36 16:38 06:16 17:04 06:38 18:39 07:06 20:26 07:15 21:27 07:08 23:15 08:43 23:20 09:54 28 16:20 01:50 17:49 03:45 16:27 02:37 16:51 04:43 16:36 05:34 17:26 07:08 17:57 07:19 19:35 07:38 21:28 07:49 22:31 07:55 ––:–– 09:50 23:56 11:01 29 17:23 02:47 17:06 03:44 17:25 05:44 17:14 06:32 18:16 07:55 18:52 07:57 20:33 08:09 22:31 08:27 23:31 08:49 00:01 10:57 ––:–– 12:05 30 18:22 03:51 17:43 04:49 18:00 06:45 17:56 07:28 19:09 08:39 19:48 08:31 21:31 08:40 23:34 09:10 ––:–– 09:48 00:42 12:03 00:29 13:08

31 19:15 04:59 18:18 05:54 18:42 08:22 20:44 09:04 22:32 09:13 00:26 10:52 01:03 14:10

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32 Lunar Occultations BAA Handbook 2018

SUN’S SELENOGRAPHIC COLONGITUDEDay Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 76.1 92.9 73.7 91.2 97.1 115.6 122.3 141.1 159.8 165.8 183.5 188.6 2 88.2 105.1 85.8 103.4 109.3 127.8 134.5 153.3 171.9 178.0 195.7 200.7 3 100.3 117.2 98.0 115.5 121.5 140.0 146.7 165.5 184.2 190.2 207.9 212.9 4 112.4 129.3 110.1 127.7 133.7 152.2 158.9 177.7 196.4 202.4 220.0 225.1 5 124.6 141.5 122.2 139.9 145.8 164.4 171.1 190.0 208.6 214.6 232.2 237.3

6 136.7 153.6 134.4 152.1 158.0 176.7 183.3 202.2 220.8 226.8 244.4 249.5 7 148.8 165.8 146.6 164.2 170.2 188.9 195.5 214.4 233.0 239.0 256.6 261.7 8 161.0 177.9 158.7 176.4 182.4 201.1 207.8 226.6 245.3 251.2 268.9 273.9 9 173.1 190.1 170.9 188.6 194.7 213.3 220.0 238.9 257.5 263.4 281.1 286.0 10 185.3 202.3 183.1 200.8 206.9 225.6 232.2 251.1 269.7 275.6 293.3 298.2

11 197.5 214.5 195.2 213.0 219.1 237.8 244.5 263.4 282.0 287.9 305.5 310.4 12 209.6 226.7 207.4 225.2 231.3 250.1 256.7 275.6 294.2 300.1 317.6 322.6 13 221.8 238.8 219.6 237.5 243.6 262.3 269.0 287.9 306.4 312.3 329.8 334.8 14 234.0 251.0 231.8 249.7 255.8 274.6 281.3 300.1 318.7 324.5 342.0 346.9 15 246.2 263.2 244.0 261.9 268.1 286.8 293.5 312.4 330.9 336.7 354.2 359.1

16 258.4 275.4 256.2 274.1 280.3 299.1 305.8 324.6 343.1 348.9 6.4 11.3 17 270.6 287.6 268.5 286.4 292.5 311.3 318.0 336.8 355.3 1.1 18.5 23.4 18 282.7 299.8 280.7 298.6 304.8 323.6 330.2 349.0 7.5 13.3 30.7 35.6 19 294.9 312.0 292.9 310.8 317.0 335.8 342.5 1.3 19.7 25.4 42.8 47.7 20 307.1 324.2 305.1 323.0 329.2 348.0 354.7 13.5 31.9 37.6 55.0 59.8

21 319.3 336.4 317.3 335.3 341.5 0.2 6.9 25.7 44.1 49.8 67.1 72.0 22 331.5 348.6 329.5 347.5 353.7 12.5 19.1 37.9 56.2 61.9 79.3 84.1 23 343.7 0.8 341.7 359.7 5.9 24.7 31.3 50.1 68.4 74.1 91.4 96.2 24 355.8 12.9 353.9 11.9 18.1 36.9 43.5 62.3 80.6 86.2 103.5 108.3 25 8.0 25.1 6.1 24.1 30.3 49.1 55.7 74.4 92.7 98.4 115.7 120.5

26 20.1 37.2 18.3 36.2 42.5 61.3 67.9 86.6 104.9 110.5 127.8 132.6 27 32.3 49.4 30.4 48.4 54.7 73.5 80.1 98.8 117.1 122.7 139.9 144.7 28 44.4 61.5 42.6 60.6 66.9 85.7 92.3 111.0 129.3 134.8 152.1 156.9 29 56.6 54.8 72.8 79.1 97.9 104.5 123.2 141.4 147.0 164.2 169.0 30 68.7 66.9 84.9 91.3 110.1 116.7 135.4 153.6 159.1 176.4 181.2

31 80.8 79.1 103.4 128.9 147.6 171.3 193.4

The Sun’s selenographic colongitude is numerically equal to the selenographic longitude of the morning terminator, measured towards celestial East from the mean centre of the disk. Its value is approximately 270° at New Moon, 0° at First Quarter, 90° at Full Moon, and 180° at Last Quarter, and should be quoted on observations. The IAU longitude of the visible morning or evening terminator, as appropriate, can be obtained from the Sun’s selenographic colongitude S as follows: Terminator S Longitude (IAU)New Moon to First Quarter Morning 270° to 360° 360°–S EastFirst Quarter to Full Moon Morning 0° to 90° S WestFull Moon to Last Quarter Evening 90° to 180° 180°–S EastLast Quarter to New Moon Evening 180° to 270° S–180° West

The hourly increase in S may be taken as 0.5°

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BAA Handbook 2018 Lunar Occultations 33

LUNAR OCCULTATIONSExcept near new and full Moon, occultations of all stars down to magnitude 6.0, visible from the three pairs of stations whose co–ordinates are tabulated below, are given in the following lists. ZC numbers refer to the Zodiacal Catalog (Astron. Papers of the American Ephemeris, X, part II, 1940).

Long. (λ) Lat. (φ) Long. (λ) Lat. (φ) ° ° ° ° Greenwich 0.0 +51.5 Edinburgh –3.2 +56.0

Sydney +151.2 –33.9 Melbourne +145.1 –37.9 Dunedin +170.5 –45.9 Wellington +174.8 –41.3

Phase (Ph.). The first letter indicates whether disappearance (D) or reappearance (R). The second letter indicates whether the limb is dark (D) or bright (B).Column 7 gives the percentage Illumination of the Moon.CA is the cusp angle of the star, measured to the celestial east (anticlockwise) from the northernmost point of the Moon’s limb.The time (T) of occultation at a place Δλ degrees east and Δφ degrees north of one of the stations for which a prediction is given may be found from:

T = predicted time + a Δλ + b Δφfor which the coefficients a and b are given in the table in minutes. If the observer is west of the station, Δλ is taken as negative: similarly Δφ is negative if the observer is south of the station. For distances up to 500 km the error will not usually exceed 2 minutes.

If the observer is at a place between two standard stations, for both of which the coefficients a and b are given, a better result can be obtained by using the values of a and b for a latitude midway between that of the observer and the nearer station. If φ1, a1, b1 apply to this station, and (φ2, a2,b2 to the more distant, and φ is the latitude of the observer, then

Observers should note that these calculations are prone to error propagation and are best done using a spreadsheet or appropriate app. Suitable support is available on the BAA website.

Notes: Predictions have been prepared using Occult 4 software.

For stars not identified by a Greek letter, Flamsteed number or variable star designation, the HIP catalogue number is provided.

When an occultation is given for one station of a pair, but not the other, the exclusion indicates the event is probably not observable at that station due to a miss, Moon elevation too low, sky too bright, or the event occurs on the bright limb. Observability is determined by a sophisticated algorithm in ‘Occult 4’.

A more detailed list of occultations is printed monthly in the Lunar Section Circulars, available on the BAA web site. Alternatively, keen observers may like to download Occult to generate predictions for their site, from: http://www.lunar-occultations.com/iota/occult4.htm (free for non–commercial use).

Further links can be found on the Internet Resources Page.

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34 Lunar Occultations BAA Handbook 2018

Lunar Occultations LUNAR OCCULTATIONS GREENWICH EDINBURGH E 0.0º N 51.5º W 3.2º N 56.0º

Date Star V Ph. Ill. of2018 ZC Name Moon UT a b CA UT a b CA º h m m/º m/º º h m m/º m/º º

Jan. 4 1434 ψ Leo 5.4 RD –89 20 47.4 +0.3 +0.1 60N 20 45.4 +0.4 –0.7 39N 5 1487 Regulus 1.4 DB –85 8 24.2 +0.1 –1.7 –87N 8 16 +0.2 –1.7 –84N 5 1487 Regulus 1.4 RD –85 9 18.7 –0.1 –1.6 89N 9 11.4 +0 –1.7 86N 25 444 HIP 51626 5.9 DD +59 17 35.7 +1.4 +0.9 84S 17 36.6 +1.1 +1.2 84N 25 462 HIP 14764 6.0 DD +61 23 25.1 +0.6 –0.2 64N 23 23.6 +0.6 +0.4 49N 27 741 HIP 23043 5.5 DD +80 18 24.5 +4.6 –9.2 12S 18 11.1 +1.4 +0.0 44S 29 947 71 Ori 5.2 DD +91 1 25.9 +0.5 –2.0 58S 1 15.7 +0.6 –1.7 69SFeb. 8 2223 γ Lib 3.9 RD –45 4 15.0 +1.6 +1.5 63S 4 17.0 +1.2 +1.4 70S 12 2757 ξ1 Sgr 5.0 RD –11 5 42.6 +0.5 +0.8 54N 21 405 μ Cet 4.3 DD +32 17 29.1 +9.9 +9.9 2N 22 508 5 Tau 4.1 DD +41 12 18.8 +0.1 +2.0 62N 12 28.1 +0.0 +2.1 54N 23 669 θ1 Tau 3.8 DD +53 12 58.9 +0.3 +1.3 69S 13 4.4 +0.2 +1.5 78S 23 669 θ1 Tau 3.8 RB +53 13 50.6 +0.1 +2.2 –55S 23 671 θ2 Tau 3.4 DD +53 13 7.1 +0.7 +0.6 42S 13 9.6 +0.4 +1.1 54S 23 671 θ2 Tau 3.4 RB +53 13 40.8 –0.3 +2.9 –28S 13 52.9 +0 +2.4 –42S 23 677 HIP 21029 4.8 DD +53 13 52.7 +0.4 +1.6 89S 13 59 +0.3 +1.8 82N 23 692 Aldebaran 0.9 DD +54 16 37.2 +1.4 +0.6 73S 16 37 +1.1 +1.1 87S 23 692 Aldebaran 0.9 RB +55 17 44.2 +1.2 +1.6 –59S 17 46.6 +1.1 +1.1 –74S 24 832 119 Tau 4.3 DD +65 15 10.8 +0.4 +2.0 64N 15 19.4 +0.2 +2.2 52N 28 1434 ψ Leo 5.4 DD +98 17 53.4 +0.2 +1.6 63N 18 1.4 +0.1 +2.1 48NMar. 1 1487 Regulus 1.4 DD +99 6 8.7 –0.2 –1.5 81N 6 2.5 –0.1 –1.5 78N 5 1950 80 Vir 5.7 RD –88 3 8.2 +1.1 –1.2 60N 3 0.1 +0.9 –1.0 55N 11 2708 HIP 91438 5.9 RD –34 4 35.5 +1.4 +1.9 64S 4 39.7 +1.1 +1.8 69S 15 3237 ι Aqr 4.3 RD –5 8 41.8 +1.5 +0.9 62N 8 41.8 +1.2 +1.0 56N 20 364 ξ2 Cet 4.3 DD +11 14 42.7 +1.8 –0.5 67S 14 37.2 +1.4 +0.2 82S 22 667 75 Tau 5.0 DD +30 20 19.2 +0.6 –2.1 63S 20 8.9 +0.7 –1.6 77S 22 692 Aldebaran 0.9 DD +31 23 38.4 –0.5 –2.1 47S 23 30.8 –0.3 –1.9 57S 23 692 Aldebaran 0.9 RB +31 0 14.3 –0.1 –0.6 –56S 23 832 119 Tau 4.3 DD +41 22 42.6 +0.1 –1.9 68S 22 33.9 +0.2 –1.7 77S 23 836 120 Tau 5.7 DD +42 23 18.7 –0.2 –2.1 54S 23 9.8 +0.0 –2.0 63SApr. 4 2247 η Lib 5.4 RD –86 2 12.2 +1.9 +0.7 68S 2 10.1 +1.5 +0.7 73S 8 2797 π Sgr 2.9 RD –51 3 22.5 +1.2 +1.2 80N 3 24.8 +0.9 +1.3 76N 20 913 64 Ori 5.1 DD +25 15 38.0 +1.4 +0.7 75N 15 38.3 +1.2 +1.2 60N 20 940 68 Ori 5.8 DD +27 20 3.1 +0.9 –0.7 64N 19 57.6 +0.9 –0.4 53NMay 8 3126 ι Cap 4.3 RD –50 2 55.4 +0.7 +0.0 19N 2 53.1 +0.2 –0.7 7NJun. 17 1434 ψ Leo 5.4 DD +23 22 28.9 –0.8 –3.1 18S 24 2247 η Lib 5.4 DD +90 23 32.3 +1.4 –1.1 81N 23 23.3 +1.3 –0.9 78N 28 2779 ο Sgr 3.8 RD –99 22 42.1 +1.7 +1.7 63S 22 44.6 +1.4 +1.6 68S

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BAA Handbook 2018 Lunar Occultations 35

Jul. 2 3171 γ Cap 3.7 RD –87 1 54.4 +0.7 +2.2 23S 3 3288 50 Aqr 5.8 RD –80 0 8.4 +0.9 +1.9 80S 0 14.1 +0.8 +1.8 84S 4 3419 ψ1 Aqr 4.2 RD –71 2 49.5 +6.1 –6.6 9N 4 3425 ψ2 Aqr 4.4 RD –71 4 31.1 +1.3 +0.8 74S 4 29.9 +1.3 +0.6 84S 8 405 μ Cet 4.3 RD –28 12 9.6 +0.5 –2.3 49N 11 54.5 +0.6 –3.9 28N 9 508 5 Tau 4.1 RD –20 6 36.8 +0.4 +3.0 36S 6 46.3 +0.6 +2.1 52S 10 635 γ Tau 3.7 RD –13 2 34.3 –0.6 +2.3 28SAug. 5 444 HIP 51626 5.9 RD –47 0 58.0 +0.3 +1.5 71N 1 3.9 +0.3 +1.5 63N 7 764 104 Tau 4.9 RD –23 8 4.4 +2.3 –5.1 24N 18 2291 49 Lib 5.5 DD +55 19 25.3 +1.7 –0.5 69N 21 2704 HIP 91347 5.9 DD +82 22 48.4 +0.8 +0.3 35N 22 49.0 +0.4 +1.0 20NSep. 14 2247 η Lib 5.4 DD +29 20 28.8 +0.5 –1.3 64N 20 21.1 +0.6 –1.3 57N 21 3171 γ Cap 3.7 DD +90 20 26.8 +1.9 +0.0 36S 20 22.6 +1.5 +0.5 44S 22 3190 δ Cap 2.9 DD +91 1 12.5 +3.2 –7.1 11S 23 3419 ψ1 Aqr 4.2 DD +98 21 6.9 –0.6 +4.7 28N 23 3425 ψ2 Aqr 4.4 DD +98 21 41.4 +1.5 +1.0 64S 21 42.1 +1.2 +1.2 71S 27 364 ξ2 Cet 4.3 RD –92 21 17.8 +0.4 +1.7 88N 21 24.1 +0.3 +1.7 82N 28 405 μ Cet 4.3 RD –90 7 15.8 +0.4 –1.1 82S 30 650 63 Tau 5.6 RD –75 2 12.9 +1.5 +0.5 74N 2 9.5 +1.5 +0.1 58NOct. 1 940 68 Ori 5.8 RD –55 22 30.0 –0.7 +2.3 26S 22 41.3 –0.5 +1.9 38S 2 995 ν Gem 4.1 RD –52 6 30.3 +1.3 +2.2 34S 3 1113 56 Gem 5.1 RD –42 2 34.8 +1.1 –0.2 51N 2 24.9 +2.4 –5.0 20N 3 1127 61 Gem 5.9 RD –41 5 13.5 +1.4 +0.6 84S 5 11.4 +1.2 +0.3 82N 28 764 104 Tau 4.9 RD –86 2 48.4 +1.0 +2.5 30S 28 895 57 Ori 5.9 RD –79 20 58.9 –0.8 +2.7 18S 21 11.4 –0.5 +2.1 32S 29 915 χ2 Ori 4.6 RD –78 1 0.7 +0.4 +3.5 24S 1 11.9 +0.6 +2.4 43S 30 1077 ζ Gem 4.0 RD –68 0 58.9 +0.6 +2.0 58S 1 5.1 +0.6 +1.6 72SNov. 21 405 μ Cet 4.3 DD +97 20 49.0 +1.0 +1.7 90S 20 54.3 +0.7 +1.8 79N 25 894 χ1 Ori 4.4 RD –95 6 16.7 +0.5 –1.0 66S 6 9.9 +0.5 –1.2 75S 26 1077 ζ Gem 4.0 RD –87 9 11.4 +0.1 –1.1 61S 27 1193 85 Gem 5.4 RD –80 4 15.1 +1.6 +2.3 30S 30 1576 53 Leo 5.3 RD –48 3 25.2 +1.1 +1.5 60S 3 27.9 +0.9 +1.1 74SDec. 19 364 ξ2 Cet 4.3 DD +82 0 44.1 +0.8 –5.3 19S 0 26.2 +0.8 –2.5 45S 19 462 HIP 14764 6.0 DD +89 18 21.3 +1.0 +1.3 68S 18 24.7 +0.8 +1.5 78S 21 650 63 Tau 5.6 DD +96 3 29.6 +0.1 –2.5 37S 3 18.7 +0.3 –2.1 50S 21 764 104 Tau 4.9 DD +99 19 23.1 +1.4 –0.1 24S 19 21.8 +0.8 +0.9 40S 25 1310 δ Cnc 3.9 RD –91 8 28.7 +0.3 –0.9 44S 8 23.3 +0.3 –1.1 49S

Lunar Occultations LUNAR OCCULTATIONS GREENWICH EDINBURGH E 0.0º N 51.5º W 3.2º N 56.0º

Date Star V Ph. Ill. of2018 ZC Name Moon UT a b CA UT a b CA ° h m m/° m/° ° h m m/° m/° °

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36 Lunar Occultations BAA Handbook 2018

Jan. 2 1113 56 Gem 5.1 RD –100 15 27.2 +2.4 +1.6 36S 13 2372 φ Oph 4.3 RD –14 2 42.9 +1.5 –1.3 54N 2 36.8 +1.5 –0.4 68N 13 2460 HIP 83854 6.0 RD –9 17 50.9 –1.2 –4.2 19N 24 249 ν Psc 4.5 DD +43 4 12.3 +1.3 –0.7 79S 4 8.7 +1.1 –1.2 71S 30 1193 85 Gem 5.4 DD +99 14 58.5 +1.7 +0.3 88S 14 47.9 +1.6 –0.1 73SFeb. 2 1576 53 Leo 5.3 RD –95 10 59.5 +0.3 +0.3 34S 23 648 δ1 Tau 3.8 DD +52 13 0.7 +0.9 +2.1 63N 23 653 64 Tau 4.8 DD +52 13 27.6 +0.5 +1.3 88S 26 1113 56 Gem 5.1 DD +83 11 14.4 +1.9 –1.3 51S 11 9.8 +1.8 –2.2 36S 26 1127 61 Gem 5.9 DD +84 14 1.2 +0.7 –0.4 53S 14 1.2 +0.3 –1.6 30SMar. 6 2141 18 Lib 5.9 RD –75 20 0.8 +1.9 –0.4 77N 8 2372 φ Oph 4.3 DB –58 13 50.3 –0.2 –2.2 –50S 14 2.3 –0.5 –2.7 –32S 8 2372 φ Oph 4.3 RD –58 14 45.8 +0.8 –0.9 72S 14 43.2 +0.8 –0.3 52S 14 3177 44 Cap 5.9 DB –7 19 23.0 +0.5 –1.4 –63S 15 3206 μ Cap 5.1 RD –6 3 48.6 +0.4 +2.8 53S 3 34.4 +0.6 +2.9 51S 20 322 64 Cet 5.6 DD +9 8 13.6 +1.0 +0.9 70S 20 327 ξ1 Cet 4.4 DD +9 9 10.0 +0.6 +1.6 81N 8 59.8 +0.8 +1.5 89N 21 454 ξ Ari 5.6 DD +16 9 36.1 +1.0 +3.3 33N 9 18.6 +1.1 +2.5 48NApr. 9 2981 π Cap 5.1 RD –37 15 39.5 +0.5 +0.0 69S 15 33.9 +0.7 +1.2 44S 9 2987 ρ Cap 4.9 RD –36 16 27.3 –0.1 –2.9 34N 14 3526 27 Psc 4.9 RD –5 1 3.1 +2.3 +0.9 75N 0 46.7 +2.1 +0.6 76N 14 3535 29 Psc 5.1 RD –5 3 26.0 +1.6 +1.1 60N 3 11.3 +1.8 +1.0 61N 25 1576 53 Leo 5.3 DD +78 15 6.8 +0.6 +1.0 70N 15 0.2 +0.6 +0.4 89N 30 2141 18 Lib 5.9 RD –100 12 20.7 +1.3 –1.8 36NMay 12 170 33 Cet 6.0 RD –9 18 53.9 +0.0 +2.9 36S 13 192 89 Psc 5.1 RD –8 0 13.3 +1.7 +1.6 76S 23 57.7 +1.5 +1.3 75S 31 2639 16 Sgr 6.0 RD –96 18 39.9 +1.3 +1.7 83S 18 23.8 +1.5 +2.1 75SJun. 2 2886 56 Sgr 4.9 RD –86 11 7.0 +0.2 –0.6 84S 11 7.1 +0.3 –0.1 65S 3 3017 υ Cap 5.2 RD –79 13 7.6 +0.7 –1.0 80N 13 6.8 +0.6 –0.5 82S 5 3268 42 Aqr 5.3 RD –61 12 57.3 +0.2 +0.6 61S 6 3421 χ Aqr 4.9 DB –49 20 22.1 +1.9 +1.7 –74N 20 4.6 +1.8 +1.3 –76N 6 3421 χ Aqr 4.9 RD –49 21 50.0 +1.9 +1.5 89N 21 32.4 +2.0 +1.3 90N 9 249 ν Psc 4.5 DB –20 18 38.8 +0.8 +0.0 –86N 18 35.5 +0.6 –0.5 –86S 9 249 ν Psc 4.5 RD –20 19 50.5 +1.3 +0.1 87S 19 43.1 +1.0 +0.1 82S 29 2886 56 Sgr 4.9 RD –98 20 36.6 +0.0 +1.7 81S 20 28.9 +0.2 +1.9 79S 30 2994 ο Cap 5.9 RD –95 16 13.8 +2.9 –0.7 61N 15 59.4 +2.5 –0.4 70NJul. 2 3237 ι Aqr 4.3 DB –83 13 56.0 +1.3 –6.4 –19S 2 3237 ι Aqr 4.3 RD –83 14 27.1 +1.4 +6.0 25S 5 76 14 Cet 5.9 RD –55 21 9.5 +2.4 +0.8 69N 20 52.1 +2.4 +0.5 69N 23 2399 24 Oph 4.9 DD +83 8 7.2 –2.5 –9.6 5S 25 2666 21 Sgr 4.9 DD +95 8 50.7 +0.6 –3.1 44S 9 8.5 –1.3 –7.8 10S 28 3079 θ Cap 4.1 DB –99 14 49.9 +2.9 –0.5 –67S 14 36.1 +2.7 –1.4 –57S 28 3079 θ Cap 4.1 RD –99 16 10.2 +1.3 +2.9 52S 15 49.9 +1.4 +3.1 47S

Lunar Occultations LUNAR OCCULTATIONS SYDNEY MELBOURNE E 151.2º S 33.9º E 145.1º S 37.9º

Date Star V Ph. Ill. of2018 ZC Name Moon UT a b CA UT a b CA ° h m m/° m/° ° h m m/° m/° °

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BAA Handbook 2018 Lunar Occultations 37

Aug. 21 2639 16 Sgr 6.0 DD +79 11 52.1 +2.3 +0.4 86S 11 37.6 +2.4 –0.4 73S 25 3181 45 Cap 6.0 DD +99 17 4.8 +0.9 +1.7 83S 16 51.5 +1.2 +1.7 82S 27 3421 χ Aqr 4.9 RD –99 16 33.6 +2.7 +0.2 68N 16 16.3 +2.8 +0.0 68N 30 249 ν Psc 4.5 DB –83 16 36.9 +2.7 –0.2 –73S 16 22.7 +2.4 –0.5 –73S 30 249 ν Psc 4.5 RD –83 17 51.8 +1.3 +2.5 44S 17 35.2 +1.2 +2.1 44SSep. 2 658 68 Tau 4.3 RD –52 23 10.6 +1.3 +1.7 72S 22 54.5 +1.5 +2.0 61S 19 2886 56 Sgr 4.9 DD +74 14 51.9 +0.2 +1.7 77N 14 43.0 +0.4 +1.8 80N 20 2994 ο Cap 5.9 DD +81 10 41.1 +1.5 +4.8 35N 10 14.7 +2.0 +2.9 49N 20 3017 21 Cap 5.2 DD +82 16 45.4 +0.1 +0.7 61S 16 41.0 +0.3 +0.8 58S 22 3237 ι Aqr 4.3 DD +93 8 48.1 +1.6 –3.0 37S 8 57.7 +1.2 –8.2 10S 22 3237 ι Aqr 4.3 RB +93 9 46.0 +1.6 +2.8 –49S 9 21.0 +1.2 +7.5 –24S 25 76 14 Cet 5.9 RD –100 15 5.8 +2.3 +0.9 66S 14 48.8 +2.2 +0.6 67S 27 322 64 Cet 5.6 RD –93 13 7.6 +4.8 –9.2 29N 28 454 HIP 14439 5.6 RD –87 16 7.5 +3.0 –0.9 63N 15 54.4 +2.7 –1.2 64NOct. 11 2133 ξ Lib 5.5 DD +6 8 19.3 +0.6 +0.9 89N 11 2133 ξ Lib 5.5 RB +6 9 16.3 +0.3 +0.8 –84N 13 2399 24 Oph 4.9 DD +19 8 25.6 +1.0 +7.9 23N 13 2399 24 Oph 4.9 RB +19 8 51.5 +2.1 –6.0 –15N 17 2963 σ Cap 5.3 DD +57 14 21.8 +0.1 +1.0 74S 14 16.1 +0.4 +1.1 71S 18 3079 θ Cap 4.1 DD +66 12 44.4 +1.1 +1.5 84S 12 30.7 +1.4 +1.4 83S 18 3079 θ Cap 4.1 RB +66 13 53.9 +0.3 +1.9 –75S 13 43.6 +0.5 +2.1 –74S 28 847 ζ Tau 3.0 DB –82 13 23.3 +0.5 +0.2 –51N 13 21.0 +0.3 –0.1 –54N 28 847 ζ Tau 3.0 RD –82 14 28.0 +1.7 –1.2 81N 14 23.4 +1.3 –1.2 84NNov. 3 1702 ν Vir 4.0 DB –16 23 42.8 +1.9 –0.4 –85N 4 1702 ν Vir 4.0 RD –16 0 59.9 +1.2 –0.7 77N 0 52.4 +1.6 +0.0 82S 12 2759 ξ2 Sgr 3.5 DD +20 7 1.2 +2.1 +1.5 79N 6 43.1 +2.3 +0.8 89N 12 2759 ξ2 Sgr 3.5 RB +21 8 26.8 +1.6 +0.9 –81N 8 12.5 +1.7 +1.1 –87N 15 3126 ι Cap 4.3 DD +46 2 0.4 +0.2 –0.8 84S 17 3421 χ Aqr 4.9 DD +69 15 48.0 –0.3 +2.6 46N 26 1110 δ Gem 3.5 RD –85 13 21.9 +0.9 –0.6 67S 13 19.6 +0.6 –0.7 63S 27 1277 η Cnc 5.3 RD –75 19 4.0 +1.8 –0.4 78NDec. 1 1773 16 Vir 5.0 RD –30 22 6.9 +2.8 +0.6 58S 21 38.9 +5.5 +4.4 22S 5 2133 ξ Lib 5.5 RD –6 0 42.4 +2.3 –0.4 79S 0 27.7 +2.6 +0.4 56S 12 3126 ι Cap 4.3 DD +23 12 57.3 +0.6 –1.4 19S 13 3237 ι Aqr 4.3 DD +31 11 7.2 +0.3 +1.9 77N 10 56.4 +0.6 +2.0 78N 13 3237 ι Aqr 4.3 RB +31 12 10.1 +0.1 +1.4 –84N 12 2.9 +0.3 +1.6 –87N 17 170 33 Cet 6.0 DD +69 9 29.6 +2.4 +0.6 79S 17 192 89 Psc 5.1 DD +70 14 53.3 +0.3 +2.4 59N 14 41.9 +0.5 +2.2 67N 24 1224 μ Cnc 5.3 RD –95 17 24.2 +0.4 –2.8 21N

Lunar Occultations LUNAR OCCULTATIONS SYDNEY MELBOURNE E 151.2º S 33.9º E 145.1º S 37.9º

Date Star V Ph. Ill. of2018 ZC Name Moon UT a b CA UT a b CA º h m m/º m/º º h m m/º m/º º

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38 Lunar Occultations BAA Handbook 2018

Jan. 2 1113 56 Gem 5.1 RD –100 16 1.6 +1.5 +1.9 42S 11 2198 HIP 75352 5.7 RD –24 14 44.9 –0.1 –1.8 79N 14 35.7 –0.1 –2.0 68N 13 2372 φ Oph 4.3 RD –14 2 52.4 +0.3 +1.6 72S 20 3307 σ Aqr 4.8 DD +9 7 52.2 +0.5 +1.3 67S 22 3526 27 Psc 4.9 DD +22 2 0.2 +1.2 +0.1 79N 2 7.3 +1.3 +0.8 68N 22 3535 29 Psc 5.1 DD +23 4 32.5 +1.1 +1.9 53N 4 47.0 +1.0 +2.4 47N 30 1193 85 Gem 5.4 DD +99 15 15.2 +0.8 +0.8 81S 15 23.0 +0.9 +1.1 84NFeb. 26 1113 56 Gem 5.1 DD +83 11 50.7 +0.6 –0.7 36S 11 52.2 +0.9 –0.2 54SMar. 8 2372 φ Oph 4.3 DB –58 14 20.2 +0.3 –2.7 –44S 14 10.5 +0.6 –2.3 –60S 8 2372 φ Oph 4.3 RD –58 15 20.0 +1.6 –0.6 65S 15 23.1 +1.6 –1.1 83S 20 322 64 Cet 5.6 DD +9 8 15.1 +0.2 +0.6 42S Apr. 9 2981 π Cap 5.1 DB –37 15 17.7 –0.2 –4.5 –19S 15 2.9 +0.3 –2.6 –44S 9 2981 π Cap 5.1 RD –37 15 50.8 +1.5 +2.2 38S 16 1.6 +1.4 +0.4 63S 9 2987 ρ Cap 4.9 DB –37 16 2.0 +1.1 +0.2 –62N 16 13.7 +1.8 +3.1 –36N 9 2987 ρ Cap 4.9 RD –36 17 4.0 +1.2 –2.7 46N 16 52.2 +1.1 –5.4 21N 14 3526 27 Psc 4.9 RD –5 1 7.2 +0.6 +2.7 49S 1 22.3 +0.7 +2.7 53S 27 1773 16 Vir 5.0 DD +92 6 58.4 +1.3 –0.4 24N May 2 2372 φ Oph 4.3 RD –94 7 58.6 –0.3 –1.6 69N 7 50.0 –0.3 –1.7 58N 2 2399 24 Oph 4.9 RD –93 13 48.2 +3.9 +5.4 38S 8 3177 44 Cap 5.9 RD –45 13 1.3 –0.1 –1.5 64N 12 52.4 –0.2 –2.1 46N 31 2639 16 Sgr 6.0 RD –96 18 25.3 –1.9 +8.5 18SJun. 1 2734 29 Sgr 5.2 RD –93 8 17.7 +0.6 +0.6 41S 8 19.6 +0.3 –0.3 64S 2 2886 56 Sgr 4.9 RD –86 11 25.5 +1.0 –0.3 67S 11 27.5 +1.1 –0.8 86S 3 3017 υ Cap 5.2 RD –79 13 35.9 +1.4 +0.1 71S 13 41.9 +1.7 –0.4 88S 5 3268 42 Aqr 5.3 RD –61 13 3.3 +0.9 +1.7 44S 6 3421 χ Aqr 4.9 RD –49 21 40.9 +0.2 +3.2 35S 21 56.4 +0.2 +3.1 40S 9 249 ν Psc 4.5 DB –20 19 26.4 +3.4 –3.3 –32S 9 249 ν Psc 4.5 RD –20 20 1.5 –0.4 +4.0 21S 28 2734 29 Sgr 5.2 RD –100 17 25.5 +0.5 +1.7 69N 17 34.8 +0.4 +1.4 62N 29 2886 56 Sgr 4.9 RD –98 19 57.0 –1.8 +5.2 19S 30 2963 σ Cap 5.3 RD –95 9 20.7 +1.9 +3.6 33S 30 2994 ο Cap 5.9 RD –95 16 37.0 +1.0 +2.5 62S 16 52.5 +1.1 +2.3 69SJul. 6 192 89 Psc 5.1 DB –46 16 37.8 –2.1 +8.4 –6N 6 192 89 Psc 5.1 RD –46 16 54.0 +4.7 –8.4 19N 7 322 64 Cet 5.6 RD –34 19 31.6 +2.4 –0.7 53N 19 39.3 +2.8 –0.8 48N 7 327 ξ1 Cet 4.4 DB –34 19 58.7 –0.1 +3.3 –20N 7 327 ξ1 Cet 4.4 RD –34 20 33.3 +3.1 –1.3 32N 20 39.8 +4.1 –2.8 24N 15 1418 8 Leo 5.7 RB +6 5 16.5 1.0 +0.4 –84N 21 2141 18 Lib 5.9 DD +65 6 26.3 +0.6 –3.0 38S 6 18.3 +1.2 –2.3 58S 29 3181 45 Cap 6.0 RD –98 9 23.7 +0.5 –2.4 52N 9 11.6 +0.3 –4.1 29N

Lunar Occultations LUNAR OCCULTATIONS DUNEDIN WELLINGTON E 170.5º S 45.9º E 174.8º S 41.3º

Date Star V Ph. Ill. of2018 ZC Name Moon UT a b CA UT a b CA º h m m/º m/º º h m m/º m/º º

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BAA Handbook 2018 Lunar Occultations 39

LUNAR OCCULTATIONS DUNEDIN WELLINGTON E 170.5º S 45.9º E 174.8º S 41.3º

Date Star V Ph. Ill. of2018 ZC Name Moon UT a b CA UT a b CA º h m m/º m/º º h m m/º m/º º

Aug. 21 2639 16 Sgr 6.0 DD +79 12 39.2 +1.9 –2.0 33S 22 2757 ξ1 Sgr 5.0 DD +85 6 38.5 +0.0 –7.1 12S 24 3017 υ Cap 5.2 DD +96 7 12.7 +0.9 –1.1 84S 7 13.7 +1.2 –0.3 79N 25 3177 44 Cap 5.9 DD +99 16 57.3 –0.4 +3.2 37N 25 3181 45 Cap 6.0 DD +99 17 7.2 +0.8 +0.6 33S 27 3421 χ Aqr 4.9 RD –99 16 44.8 +0.7 +2.1 62S 16 57.6 +0.7 +2.1 65SSep. 18 2734 29 Sgr 5.2 DD +64 11 37.3 +0.5 +2.2 68N 11 49.5 +0.3 +2.4 59N 19 2886 56 Sgr 4.9 DD +74 14 40.4 +0.2 +0.9 55S 14 44.7 +0.0 +0.8 61S 20 2994 ο Cap 5.9 DD +81 10 48.6 +1.7 +1.1 83S 11 1.6 +1.6 +1.5 89N 26 192 89 Psc 5.1 RD –98 11 16.9 +1.7 –1.5 75N 11 17.7 +2.3 –2.0 64N 27 322 64 Cet 5.6 RD –93 14 12.1 +1.6 +0.6 75S 14 22.6 +1.8 +0.8 79S 27 327 ξ1 Cet 4.4 DB –93 14 8.6 +1.4 +0.9 –61N 14 19.6 +1.5 +1.3 –57N 27 327 ξ1 Cet 4.4 RD –93 15 26.5 +1.7 +0.8 88S 15 38.5 +1.9 +1.0 89N 28 454 HIP 14439 5.6 RD –87 16 42.3 +1.5 +1.3 71S 16 55.2 +1.6 +1.4 75SOct. 2 1047 36 Gem 5.3 RD –47 14 28.7 +0.7 –1.0 77S 11 2133 ξ Lib 5.5 DD +6 8 22.9 +0.3 –0.5 39S 8 22.7 +0.1 +0.0 54S 13 2399 24 Oph 4.9 DD +19 8 21.6 +0.5 +1.7 77N 8 31.9 +0.3 +2.0 65N 13 2399 24 Oph 4.9 RB +19 9 23.7 +0.3 +0.9 –74N 15 2638 15 Sgr 5.3 DD +35 1 25.3 +0.3 –3.2 33S 15 2666 21 Sgr 4.9 DD +36 7 47.9 +1.3 +2.2 65N 8 4.7 +0.9 +3.0 52N 15 2666 21 Sgr 4.9 RB +37 8 58.6 +1.2 +0.6 –65N 9 5.8 +1.3 +0.1 –54N 18 3079 θ Cap 4.1 DD +66 12 59.2 +2.1 –1.7 17S 13 1.8 +1.1 –0.3 28S 18 3079 θ Cap 4.1 RB +66 13 15.6 –1.6 5.1 –14S 13 29.3 –0.9 +3.5 –26S 28 847 ζ Tau 3.0 DB –82 13 53.2 +1.6 –1.1 –77S 13 56.0 +1.8 –0.9 –82S 28 847 ζ Tau 3.0 RD –82 15 2.5 +1.4 +0.3 54S 15 11.3 +1.8 +0.5 59SNov. 4 1702 ν Vir 4.0 RD –16 1 18.4 +0.7 +0.5 88S 1 21.6 +0.4 –0.2 74N 12 2759 ξ2 Sgr 3.5 DD +20 7 29.0 +1.7 –0.5 42S 7 35.2 +1.4 +0.2 53S 12 2759 ξ2 Sgr 3.5 RB +21 8 16.4 +0.0 +3.4 –40S 8 30.2 +0.0 +2.7 –50S 15 3126 ι Cap 4.3 DD +46 2 26.5 +0.8 –2.1 57S 2 22.8 +1.1 –1.3 75S 15 3126 ι Cap 4.3 RB +46 3 42.5 +1.7 –0.1 –87S 16 3268 42 Aqr 5.3 DD +57 7 46.3 –0.3 +5.6 20N 24 765 106 Tau 5.3 RD –98 10 2.0 +1.1 –1.7 79N 9 59.5 +1.5 –1.9 71N 25 976 μ Gem 2.9 DB –92 16 9.4 +1.9 2.1 –28N 25 976 μ Gem 2.9 RD –92 16 47.6 +0.8 –0.7 34N 26 1110 δ Gem 3.5 DB –86 13 8.6 +2.2 –3.3 –33S 13 4.2 +2.1 –2.6 –44S 26 1110 δ Gem 3.5 RD –86 13 38.0 +0.7 +1.4 15S 13 47.7 +1.3 +1.1 26S 27 1250 HIP 40866 5.8 RD –77 13 1.9 +0.8 –0.9 57S 13 1.9 +1.0 –0.8 63SDec. 1 1773 7 Vir 5.0 RD –30 22 37.0 +1.8 +1.8 50S 22 49.5 +1.3 +0.8 72S 5 2133 ξ Lib 5.5 RD –6 1 12.4 +1.5 +1.6 53S 1 24.1 +1.3 +0.8 72S 13 3237 ι Aqr 4.3 DD +31 10 53.6 +0.2 +1.4 64S 11 0.2 +0.0 +1.3 69S

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40 Grazing Lunar Occultations BAA Handbook 2018

Lunar Occultations GRAZING LUNAR OCCULTATIONSThe map shows the tracks of stars to magnitude 7.5 which will graze the Moon’s limb and where the Moon is less than 90 percent sunlit, has an altitude of more than 5° and a cusp Angle > 3°The track commences in the West, and the Time (UT) is near the centre of the region. Tracks marked on the map as `A´ indicate the star is at a low altitude. Tracks marked with a `B´ indicate the bright limb is close. Small or negative cusp angles indicate the graze occurs at the terminator. The track is terminated if the altitude (A) is low or when the sky (S) is bright.Both the track and time (UT) start in the West. The Altitude (Alt) column is the approximate elevation of the Moon, as a guide to observability. Details for the potential observer will be supplied.

Accuracy: Recording events to a UT accuracy of 0.5s or better are desirable. Observers using video or planetary webcams recording at 25fps or greater, with UT time stamps, are invited to contact the Lunar Section for assistance with light curve analysis and reporting of times.Visual Observers: Individuals and teams should continue to send timings to the Lunar Section.

General circumstances for the events can be judged from personal planetarium software, but those plan-ning to observe a graze should request track details from the Director of the Computing Section. More details of grazes are given in the Lunar Section Circulars, or may be computed using software for non–commercial use from: http://www.lunar-occultations.com/iota/occult4.htm http://www.doa-site.nl/

Observers positioned on or very near the tracks may see the star disappear and reappear several times at the edge of features on the Moon’s limb. The recorded times, to an accuracy of better than 0.5s, continue to be valuable in the study and refinement of the shape and motion of the Moon, and in the detection of double or multiple stars, particularly during grazes. Potential observers are encouraged to contact Tim Haymes at [email protected] for additional information and advice on how to report graze timings. A brief notification of success or failure of the observing attempt would also be helpful.

Key to the Map

2018 Star N or S Cusp name ZC* Time† V Sunlit‡ limit angle† sp§ alt. MM DD h m % °1 SAO 164817 3224 Jan. 19 17 04 7.6 6+ S 5.7 K0 152 SAO 109783 X1775 Jan. 23 17 56 7.3 37+ S 6.4 G5 403 318B Tau 741 Jan. 27 18 19 5.5 81+ S 4.8 K1 454 5 Tau 508 Mar. 21 19 51 4.1 19+ S 4.8 K0 305 SAO 93961 672 Mar. 22 20 43 6.7 29+ S 2.8 F7 326 275B Tau 685 Mar. 22 22 52 6.6 30+ S 1.0 F0 167 SAO 94586 823 Mar. 23 21 38 6.7 41+ S 1.0 A2 358 ψ Leo 1434 Jun. 17 22 35 5.4 22+ S 1.4 M2 129 ψ1 Aqr 3419 Jul. 04 02 34 4.2 71- N 2.7 K0 2510 SAO 109883 208 Aug. 03 03 27 7.0 67- N 8.5 F0 3911 SAO 94739 X7312 Sep. 04 03 48 7.6 38- N 9.5 B9 4112 56 Gem 1113 Oct. 03 02 13 5.1 41- N 9.7 M0 2513 70B Psc 3529 Dec. 15 21 41 6.5 53+ S 4.3 G5 2414 424B Leo 1684 Dec. 28 07 13 6.8 63- S 3.7 K0 34

* Numbers taken from the Robertson Zodiacal Catalog or the Extended Zodiacal Catalog d = double, m = multiple, u = unconfirmed.† Precise times and cusp angles are dependent on location‡ a negative number indicates a waning Moon§ graze occurs against a [B]right limb, [D]ark limb, [T]erminatorsp star spectrum classificationalt. is depenedent on location and is provided as a guide

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BAA Handbook 2018 Grazing Lunar Occultations 41

Lunar Occultations GRAZING LUNAR OCCULTATIONS

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42 Mars BAA Handbook 2018

MARS

Opposition: Jul. 27

2018 RA Dec. V Diam P Q Ph. DE DS LS h m ° ' " ° ° ° ° °

Jan. –8 14 25.9 –13 27 1.6 4.6 38 289 0.939 17.4 24.3 1052 14 50.4 –15 25 1.5 4.8 39 288 0.932 15.3 23.7 110

12 15 15.2 –17 13 1.4 5.0 38 286 0.924 13.0 22.9 11422 15 40.4 –18 49 1.3 5.3 38 284 0.917 10.6 21.9 119

Feb. 1 16 5.8 –20 11 1.2 5.6 36 281 0.910 8.1 20.8 123

11 16 31.4 –21 20 1.1 5.9 35 279 0.903 5.5 19.6 12821 16 57.2 –22 15 0.9 6.3 33 276 0.897 3.0 18.2 133

Mar. 3 17 22.8 –22 55 0.8 6.8 30 274 0.891 0.4 16.6 13813 17 48.2 –23 20 0.6 7.3 28 271 0.886 –2.1 14.9 14323 18 13.2 –23 32 0.5 7.9 25 269 0.882 –4.4 13.1 148

Apr. 2 18 37.5 –23 32 0.3 8.5 22 266 0.879 –6.7 11.2 15312 19 1.0 –23 21 0.1 9.3 19 264 0.878 –8.7 9.1 15822 19 23.3 –23 02 –0.2 10.2 16 262 0.879 –10.6 7.0 164

May 2 19 44.1 –22 39 –0.4 11.2 13 260 0.883 –12.2 4.7 16912 20 3.2 –22 15 –0.6 12.4 10 259 0.889 –13.5 2.4 174

22 20 19.9 –21 55 –0.9 13.7 8 258 0.898 –14.4 0.0 180Jun. 1 20 33.9 –21 43 –1.2 15.3 6 258 0.911 –15.0 –2.4 186

11 20 44.4 –21 45 –1.5 17.0 4 258 0.927 –15.2 –4.8 19121 20 50.6 –22 06 –1.8 18.9 3 259 0.946 –14.9 –7.2 197

Jul. 1 20 51.9 –22 48 –2.2 20.9 3 263 0.966 –14.2 –9.6 203

11 20 48.0 –23 46 –2.5 22.6 4 270 0.984 –13.2 –12.0 20921 20 39.4 –24 52 –2.7 23.8 5 294 0.996 –12.0 –14.2 21531 20 28.3 –25 49 –2.8 24.3 6 22 0.997 –10.8 –16.4 222

Aug. 10 20 17.6 –26 24 –2.6 23.9 8 56 0.987 –9.9 –18.4 22820 20 10.3 –26 28 –2.4 22.8 9 66 0.969 –9.6 –20.1 234

30 20 8.3 –26 05 –2.2 21.2 9 70 0.946 –9.9 –21.7 240Sep. 9 20 12.0 –25 18 –1.9 19.4 9 73 0.923 –10.8 –23.0 247

19 20 21.0 –24 13 –1.6 17.7 8 73 0.904 –12.2 –24.0 25329 20 34.3 –22 51 –1.4 16.1 6 73 0.887 –13.9 –24.7 259

Oct. 9 20 50.9 –21 14 –1.1 14.6 3 73 0.875 –15.8 –25.1 266

19 21 10.0 –19 22 –0.9 13.3 0 72 0.867 –17.8 –25.2 27229 21 30.8 –17 17 –0.7 12.2 357 71 0.861 –19.7 –24.9 278

Nov. 8 21 52.8 –15 00 –0.5 11.2 353 70 0.858 –21.5 –24.3 28418 22 15.6 –12 31 –0.3 10.3 349 69 0.858 –23.1 –23.5 29128 22 38.9 –9 54 –0.1 9.5 346 68 0.859 –24.5 –22.4 297

Dec. 8 23 2.5 –7 09 0.1 8.8 342 67 0.862 –25.4 –21.0 30318 23 26.4 –4 19 0.3 8.2 338 67 0.866 –26.0 –19.4 30928 23 50.5 –1 27 0.4 7.6 334 67 0.871 –26.2 –17.7 314

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BAA Handbook 2018 Mars 43

LONGITUDE OF THE CENTRAL MERIDIAN OF MARS

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.° ° ° ° ° ° ° ° ° ° ° °

1 227.5 287.6 17.8 79.8 152.5 218.6 301.4 24.6 106.3 186.6 249.1 316.22 217.8 278.0 8.1 70.2 143.0 209.3 292.3 15.8 97.2 177.1 239.4 306.43 208.1 268.3 358.5 60.6 133.4 199.9 283.2 6.9 88.0 167.6 229.7 296.54 198.4 258.7 348.9 51.0 123.9 190.5 274.2 358.0 78.8 158.1 220.0 286.75 188.7 249.0 339.3 41.4 114.3 181.1 265.2 349.2 69.6 148.6 210.3 276.96 179.0 239.4 329.7 31.8 104.8 171.8 256.1 340.3 60.4 139.1 200.6 267.07 169.3 229.7 320.0 22.2 95.3 162.5 247.1 331.4 51.2 129.6 190.9 257.28 159.7 220.1 310.4 12.6 85.8 153.1 238.1 322.5 42.0 120.0 181.1 247.49 150.0 210.4 300.8 3.0 76.2 143.8 229.1 313.6 32.7 110.5 171.4 237.510 140.3 200.8 291.2 353.4 66.7 134.5 220.2 304.7 23.5 100.9 161.7 227.711 130.6 191.2 281.6 343.9 57.2 125.2 211.2 295.8 14.2 91.4 151.9 217.812 120.9 181.5 271.9 334.3 47.7 115.9 202.3 286.9 4.9 81.8 142.2 208.013 111.2 171.9 262.3 324.7 38.2 106.6 193.3 278.0 355.6 72.2 132.4 198.114 101.6 162.2 252.7 315.1 28.7 97.3 184.4 269.1 346.3 62.7 122.7 188.315 91.9 152.6 243.1 305.5 19.2 88.1 175.5 260.1 337.0 53.1 112.9 178.416 82.2 143.0 233.5 295.9 9.7 78.8 166.5 251.2 327.7 43.5 103.1 168.517 72.6 133.3 223.9 286.4 0.2 69.6 157.6 242.2 318.4 33.9 93.4 158.718 62.9 123.7 214.3 276.8 350.7 60.3 148.7 233.2 309.0 24.3 83.6 148.819 53.2 114.1 204.6 267.2 341.3 51.1 139.8 224.2 299.7 14.7 73.8 139.020 43.5 104.4 195.0 257.6 331.8 41.9 131.0 215.2 290.3 5.0 64.0 129.121 33.9 94.8 185.4 248.1 322.3 32.7 122.1 206.2 280.9 355.4 54.2 119.222 24.2 85.2 175.8 238.5 312.9 23.5 113.2 197.2 271.5 345.8 44.4 109.423 14.5 75.5 166.2 228.9 303.4 14.3 104.3 188.2 262.1 336.1 34.7 99.524 4.9 65.9 156.6 219.4 294.0 5.2 95.5 179.1 252.7 326.5 24.9 89.625 355.2 56.3 147.0 209.8 284.5 356.0 86.6 170.1 243.3 316.8 15.1 79.826 345.6 46.6 137.4 200.3 275.1 346.9 77.7 161.0 233.9 307.2 5.2 69.927 335.9 37.0 127.8 190.7 265.7 337.7 68.9 151.9 224.4 297.5 355.4 60.028 326.2 27.4 118.2 181.1 256.3 328.6 60.0 142.8 215.0 287.9 345.6 50.129 316.6 108.6 171.6 246.8 319.5 51.2 133.7 205.5 278.2 335.8 40.330 306.9 99.0 162.0 237.4 310.4 42.3 124.6 196.1 268.5 326.0 30.4 31 297.3 89.4 228.0 33.5 115.5 258.8 20.5

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h ° h ° m ° m ° m °

1 14.62 7 102.34 10 2.44 1 0.24 6 1.46 2 29.24 8 116.96 20 4.87 2 0.49 7 1.71 3 43.86 9 131.58 30 7.31 3 0.73 8 1.95 4 58.48 10 146.21 40 9.75 4 0.97 9 2.19 5 73.10 11 160.83 50 12.18 5 1.22 10 2.44 6 87.72 12 175.45 60 14.62

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44 Asteroids BAA Handbook 2018

ASTEROIDS

ORBITAL ELEMENTS

Observers with binoculars or small telescopes may find these data useful in locating some of the brighter asteroids.

The data below, for asteroids brighter than magnitude 9.6 at opposition, have been extracted from the Minor Planet Center’s Minor Planet and Comet Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox of the elements J2000Epoch of the elements JD 2457800.5, 2017 Feb. 16.0 TT

No. Name a e i Node Peri. M au º º º º 2 Pallas 2.773 0.231 34.840 173.088 309.997 248.969 3 Juno 2.668 0.257 12.990 169.859 248.223 213.983 4 Vesta 2.361 0.089 7.141 103.842 151.076 238.247 6 Hebe 2.425 0.203 14.737 138.653 239.827 237.387 7 Iris 2.385 0.231 5.523 259.569 145.344 286.320 8 Flora 2.201 0.157 5.887 110.905 285.339 313.383 20 Massalia 2.409 0.142 0.708 206.106 256.590 267.009 29 Amphitrite 2.555 0.072 6.089 356.422 62.255 92.301 30 Urania 2.366 0.127 2.095 307.541 87.233 172.496 40 Harmonia 2.267 0.047 4.257 94.194 269.777 236.506 433 Eros 1.458 0.223 10.828 304.327 178.805 319.311

WEBSITE

More information on asteroids and dwarf planets can be found on the website of the Asteroids and Remote Planets Section at:

http://www.britastro.org/asteroids/

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BAA Handbook 2018 Asteroids 45

ASTEROID EPHEMERIDESThe geocentric data below, for asteroids listed on p.44, have been extracted from the Minor Planet Center Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox of the elements J2000Epoch of the elements JD 2457800.5, 2017 Feb. 16.0 TT

2 Pallas

2018 RA Dec. Δ r Elong. V h m s º ' " au au º Jan. 1 2 33 58.6 −25 52 45 1.986 2.394 102.1 8.7 11 2 37 29.3 −24 16 09 2.064 2.372 95.6 8.8 21 2 43 33.7 −22 25 20 2.143 2.350 89.5 8.8 31 2 51 57.1 −20 25 09 2.221 2.329 83.7 8.9Feb. 10 3 02 22.9 −18 19 24 2.297 2.309 78.3 9.0 20 3 14 37.4 −16 11 03 2.371 2.290 73.2 9.0Mar. 2 3 28 27.8 −14 02 46 2.44 2.272 68.4 9.0 12 3 43 41.9 −11 56 43 2.506 2.254 63.9 9.1

Pallas in conjunction to the Sun: 2018 August 17

Nov. 17 12 10 53.9 −6 02 18 2.744 2.233 49.6 9.1 27 12 28 09.2 −6 25 38 2.657 2.249 55.5 9.1Dec. 7 12 44 44.6 −6 37 28 2.561 2.267 61.7 9.1 17 13 00 31.7 −6 35 14 2.459 2.285 68.3 9.0 27 13 15 21.1 −6 16 23 2.351 2.304 75.2 9.0

3 Juno

2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jun. 20 1 34 10.8 +7 35 02 2.442 2.193 63.8 9.9 30 1 52 24.9 +8 30 01 2.318 2.169 68.8 9.8Jul. 10 2 10 27.5 +9 14 07 2.193 2.147 73.9 9.7 20 2 28 10.1 +9 45 37 2.068 2.126 79.2 9.5 30 2 45 22.4 +10 02 52 1.943 2.106 84.6 9.4 Aug. 9 3 01 52.0 +10 04 18 1.820 2.087 90.2 9.3 19 3 17 21.1 +9 48 23 1.700 2.069 96.1 9.1 29 3 31 30.3 +9 13 56 1.584 2.053 102.4 8.9Sep. 8 3 43 56.9 +8 20 10 1.474 2.038 109.0 8.7 18 3 54 12.9 +7 06 54 1.370 2.025 116.1 8.5 28 4 01 52.3 +5 35 21 1.277 2.014 123.7 8.3Oct. 8 4 06 29.7 +3 48 21 1.195 2.004 131.8 8.1 18 4 07 46.5 +1 51 23 1.127 1.996 140.1 7.9 28 4 05 44.4 −0 06 47 1.076 1.990 148.0 7.7Nov. 7 4 00 47.5 −1 54 50 1.045 1.986 154.4 7.5 17 3 53 51.8 −3 20 05 1.036 1.984 156.9 7.4 27 3 46 20.4 −4 12 08 1.048 1.984 154.1 7.5Dec. 7 3 39 38.8 −4 25 54 1.082 1.985 147.6 7.7 17 3 35 02.1 −4 01 59 1.134 1.989 139.6 7.9 27 3 33 17.3 −3 05 59 1.203 1.994 131.3 8.1

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46 Asteroids BAA Handbook 2018

4 Vesta2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 31 16 24 58.4 −15 57 59 2.425 2.178 63.8 7.7Feb. 10 16 43 11.4 −16 32 32 2.312 2.173 69.5 7.6 20 17 00 38.3 −16 57 55 2.196 2.169 75.4 7.5Mar. 2 17 17 05.2 −17 14 57 2.078 2.165 81.4 7.4 12 17 32 18.1 −17 24 53 1.959 2.161 87.8 7.3 22 17 45 58.9 −17 29 17 1.840 2.158 94.4 7.2Apr. 1 17 57 48.2 −17 30 05 1.723 2.156 101.4 7.0 11 18 07 26.0 −17 29 36 1.609 2.154 108.9 6.9 21 18 14 28.0 −17 30 21 1.502 2.153 117.0 6.7May 1 18 18 32.4 −17 34 59 1.403 2.152 125.7 6.5 11 18 19 21.2 −17 45 54 1.315 2.152 135.1 6.2 21 18 16 43.8 −18 04 50 1.241 2.152 145.3 6.0 31 18 10 51.9 −18 32 23 1.186 2.153 156.2 5.8Jun. 10 18 02 22.4 −19 07 31 1.152 2.155 167.5 5.5 20 17 52 21.0 −19 48 00 1.142 2.157 176.4 5.3 30 17 42 18.1 −20 31 07 1.155 2.159 167.6 5.6Jul. 10 17 33 40.5 −21 14 36 1.193 2.162 156.3 5.8 20 17 27 38.5 −21 57 10 1.251 2.166 145.5 6.0 30 17 24 53.5 −22 38 18 1.328 2.170 135.3 6.3Aug. 9 17 25 35.8 −23 17 33 1.419 2.175 126.0 6.5 19 17 29 39.5 −23 54 21 1.522 2.180 117.3 6.7 29 17 36 46.6 −24 27 49 1.633 2.186 109.3 6.9Sep. 8 17 46 33.5 −24 56 47 1.750 2.192 101.9 7.1 18 17 58 38.7 −25 20 01 1.871 2.199 94.9 7.3 28 18 12 39.9 −25 36 17 1.995 2.205 88.3 7.4 Oct. 8 18 28 16.9 −25 44 25 2.119 2.213 82.0 7.5 18 18 45 13.1 −25 43 28 2.242 2.220 75.9 7.6 28 19 03 11.4 −25 32 39 2.363 2.228 70.0 7.7Nov. 7 19 21 57.6 −25 11 29 2.481 2.237 64.3 7.8 17 19 41 19.8 −24 39 41 2.595 2.245 58.7 7.9

ASTEROID EPHEMERIDES

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BAA Handbook 2018 Asteroids 47

6 Hebe2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Aug. 9 4 56 35.0 +9 28 38 2.212 1.971 63.0 10.0 19 5 16 16.0 +9 21 27 2.134 1.982 67.5 10.0 29 5 34 52.5 +9 02 52 2.053 1.994 72.3 9.9Sep. 8 5 52 12.2 +8 34 03 1.969 2.008 77.5 9.8 18 6 07 59.5 +7 56 31 1.883 2.023 83.0 9.8 28 6 21 58.7 +7 12 19 1.795 2.039 88.9 9.7Oct. 8 6 33 52.2 +6 23 52 1.706 2.056 95.4 9.6 18 6 43 18.7 +5 34 09 1.618 2.074 102.4 9.4 28 6 49 58.0 +4 46 56 1.532 2.093 110.1 9.3Nov. 7 6 53 29.5 +4 06 30 1.452 2.112 118.4 9.2 17 6 53 35.8 +3 37 59 1.381 2.133 127.5 9.0 27 6 50 14.2 +3 26 50 1.322 2.153 137.2 8.8Dec. 7 6 43 39.1 +3 37 47 1.280 2.175 147.2 8.6 17 6 34 33.8 +4 13 59 1.259 2.196 156.4 8.5 27 6 24 11.6 +5 15 06 1.263 2.218 161.9 8.4

7 Iris2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 2 8 50.6 +15 25 38 1.209 1.853 115.0 8.5 11 2 20 51.6 +15 39 39 1.311 1.862 107.6 8.8 21 2 35 04.7 +16 07 48 1.420 1.874 100.8 9.0 31 2 51 07.7 +16 45 49 1.533 1.887 94.5 9.2Feb. 10 3 08 39.5 +17 29 31 1.649 1.902 88.6 9.3 20 3 27 25.6 +18 15 20 1.768 1.918 83.0 9.5Mar. 2 3 47 12.4 +19 00 08 1.887 1.936 77.7 9.6 12 4 07 47.3 +19 41 10 2.006 1.955 72.6 9.7 22 4 29 01.4 +20 16 16 2.125 1.975 67.7 9.9Apr. 1 4 50 44.7 +20 43 38 2.243 1.996 62.9 10.0

8 Flora

2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 6 53 47.0 +20 57 38 1.032 2.014 177.0 8.2 11 6 42 21.2 +21 54 12 1.057 2.031 169.3 8.5 21 6 32 40.4 +22 45 01 1.107 2.049 156.9 8.8 31 6 26 10.4 +23 27 56 1.179 2.066 145.2 9.1Feb. 10 6 23 30.0 +24 02 43 1.271 2.084 134.4 9.4 20 6 24 43.1 +24 29 50 1.377 2.102 124.6 9.7Mar. 2 6 29 31.8 +24 49 40 1.495 2.121 115.6 10.0 12 6 37 24.7 +25 02 12 1.621 2.139 107.4 10.2 22 6 47 51.4 +25 07 04 1.753 2.158 99.8 10.4

ASTEROID EPHEMERIDES

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48 Asteroids BAA Handbook 2018

ASTEROID EPHEMERIDES

20 Massalia2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 5 26 44.3 +22 01 43 1.114 2.072 162.0 8.8 11 5 19 08.5 +21 55 50 1.158 2.069 150.1 9.1 21 5 14 56.4 +21 53 42 1.222 2.067 138.9 9.3 31 5 14 35.7 +21 56 22 1.302 2.066 128.7 9.6Feb. 10 5 18 00.9 +22 03 27 1.395 2.066 119.3 9.8 20 5 24 52.1 +22 13 23 1.498 2.067 110.8 10.0Mar. 2 5 34 43.1 +22 24 04 1.607 2.070 103.1 10.2 12 5 47 03.8 +22 33 06 1.720 2.073 95.9 10.4

29 Amphitrite2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° May 1 18 05 19.2 −31 37 59 1.987 2.733 128.7 10.4 11 18 02 34.7 −32 07 12 1.889 2.730 138.7 10.2 21 17 56 50.2 −32 32 48 1.810 2.728 149.1 10.0 31 17 48 30.1 −32 51 18 1.753 2.725 159.5 9.8Jun. 10 17 38 20.7 −32 59 22 1.720 2.722 168.4 9.6 20 17 27 28.6 −32 54 55 1.715 2.719 169.0 9.5 30 17 17 11.8 −32 38 31 1.736 2.716 160.5 9.7Jul. 10 17 08 37.6 −32 13 03 1.782 2.712 150.2 9.9 20 17 02 35.2 −31 42 36 1.851 2.708 139.8 10.1 30 16 59 30.6 −31 11 22 1.938 2.704 129.9 10.3

30 Urania2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Aug. 29 23 57 18.7 +2 26 40 1.180 2.138 154.9 10.3Sep. 8 23 49 54.4 +1 55 02 1.135 2.128 166.3 10.0 18 23 41 01.3 +1 10 26 1.114 2.118 176.8 9.6 28 23 32 01.1 +0 20 36 1.118 2.109 168.7 9.9Oct. 8 23 24 15.7 −0 25 57 1.145 2.101 157.0 10.2 18 23 18 54.5 −1 01 28 1.194 2.094 145.7 10.4

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BAA Handbook 2018 Asteroids 49

40 Harmonia2018 RA Dec. ∆ r Elong. V h m s ° ' " au au °Oct. 28 5 33 58.3 +19 58 45 1.433 2.210 130.3 10.5Nov. 7 5 31 04.9 +20 04 13 1.355 2.215 141.0 10.3 17 5 24 37.0 +20 10 33 1.295 2.220 152.5 10.0 27 5 15 11.4 +20 17 22 1.258 2.225 164.7 9.7Dec. 7 5 03 55.9 +20 24 05 1.245 2.230 176.7 9.4 17 4 52 26.5 +20 30 53 1.260 2.235 169.3 9.7 27 4 42 22.9 +20 39 02 1.302 2.240 156.9 10.0

433 Eros2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Nov. 17 4 41 07.5 +60 51 10 0.348 1.263 136.0 10.3 27 4 34 30.2 +62 10 14 0.308 1.235 138.6 10.0Dec. 7 4 23 00.2 +61 47 14 0.274 1.209 140.4 9.7 17 4 12 53.7 +59 11 54 0.246 1.186 141.2 9.4 27 4 10 32.1 +54 16 03 0.225 1.166 140.6 9.2

ASTEROID EPHEMERIDES

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50 Asteroids BAA Handbook 2018

ASTEROID OCCULTATIONS

OCCULTATIONS OF STARS BY ASTEROIDS AND DWARF PLANETSFavourable events predicted by Edwin Goffin: Max Star Asteroid Asteroid Star Date UT ΔM Duration Magnitude Diameter hh:mm s km 372 Palma UCAC4-714-42365 Jan. 10 01:09 1.8 15.8 9.1 190164 Eva UCAC4-588-41365 Oct. 31 04:34 4.1 9.3 9.0 109 38 Leda UCAC4-606-13842 Nov. 18 04:37 1.7 13.3 9.8 116 479 Caprera UCAC4-514-35495 Dec. 10 20:47 5.1 9.8 7.8 70see page 51 for Chart

In the table above: ΔM The change in V magnitude. Max Duration Duration of the occultation for an observer at the centre of the shadow path Star Magnitude Visual magnitude of the star

Four predictions are highlighted (see table above). These present reasonably good opportunities for UK observers.

Featured TNO: 1998WV31 on 2018 Jan 3 (See chart page 51 and table page 53). This Plutino is in a 2:3 resonance with Pluto at a perihelion distance of 28 AU (aphelion 50 AU. e=0.27). It is predicted to occult at 12.7 mag star in Taurus. Observers are requested to monitor the star for possible satellite occultations, and to help determine the actual ground track of the main body. Details here: http://bedekkingen.vvs.be/predictions/Asteroids2018/PDF/B18_01006.pdf

Regional predictionsPredictions are selected for :Star Mag 11.0 and brighter, Diam. >30Km, Durn. >3s, Mag-Drop >1.5 These are selected from E. Goffin’s global predictions.

TNO Global predictionsSelected TNOs events all regions

Major planetsAll major planet events are listed.

Prediction uncertaintiesPredictions published a year in advance can be uncertain by several path widths. It’s desirable to monitor appulses even when located outside nominal geographical limits as, on some occasions, the unexpected can be found. e.g. double stars or unknown satellites.

Event durationThe duration of an occultation depends on where the observer is positioned within the track. Negative and positive results are published on EURASTER.NET website : http://www.euraster.net/results/index.html – where there is a link to the BEST results.

Recording and reporting an observationObservations should be timed with a UT accuracy of typically 0.1 to 0.3 sec and reported to the Asteroids and Remote Planets Section and the PLANOCCULT list server. Negative observations (no occultation) should also be reported. European observers are strongly encouraged to subscribe to the PLANOCCULT mailing list for last-minute updates and observation reports : - visit : http://vps.vvs.be/mailman/listinfo/planoccult and follow the instructions to use the list server.

For more up-to-date information on predictions, finder charts and occultation news, consult the following home pages : http://www.iota-es.de/ - International Occultation Timing Association http://www.lesia.obspm.fr/perso/bruno-sicardy/ - Bruno Sicardy http://astro.kretlow.de - Database maintained by Mike Kretlow http://asteroidoccultations.com/2018-BestEvents.htm - Steve Preston

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BAA Handbook 2018 Asteroids 51

ASTEROID OCCULTATIONS

TNO HIGHLIGHT

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52 Asteroids BAA Handbook 2018

Jan. 4 4 36 260 Huberta 0.04 HSOY 576302327 10.79 8.2 4.8 3 4 22 22 788 Hohensteina 0.07 HIP 39882 9.27 8.9 4.0 3 9 2 11 138 Tolosa 0.04 HSOY 526366323 8.79 4.5 4.0 3, 5 11 20 25 909 Ulla 0.06 TYC 4735-00554-1 10.25 11.4 4.2 3 12 23 35 464 Megaira 0.06 HSOY 525958864 8.87 7.9 4.8 1, 3 15 22 40 2453 Wabash 0.03 TYC 1968-00445-1 10.97 4.1 5.3 3, 6 25 23 32 73 Klytia 0.04 TYC 1915-01420-1 10.38 4.2 2.3 3, 5 27 18 31 175 Andromache 0.05 HSOY 555963826 10.96 6.5 2.7 3,5,7Feb. 1 2 48 1116 Catriona 0.04 TYC 3379-00656-1 10.08 5.0 3.3 2, 3 1 21 14 657 Gunlod 0.04 TYC 4917-00021-1 10.91 5.9 3.5 3 19 16 25 114 Kassandra 0.08 TYC 1317-00217-1 9.92 24.9 2.6 3 20 22 26 577 Rhea 0.02 TYC 1401-00595-1 9.98 3.0 4.8 3 22 0 46 1032 Pafuri 0.03 HSOY 578341003 7.62 7.2 7.5 3, 5 23 18 07 211 Isolda 0.09 HIP 19146 8.50 7.8 4.5 3 23 18 57 167 Urda 0.02 HSOY 523624113 8.87 4.3 5.8 3 23 19 27 129 Antigone 0.05 HIP 22583 9.75 10.5 3.2 3, 5 28 18 12 451 Patientia 0.12 HSOY 523824041 6.22 16.6 5.7 3, 5Mar. 10 17 53 818 Kapteynia 0.03 UCAC4-618-047637 10.76 4.4 3.7 3, 5 15 2 39 578 Happelia 0.04 HSOY 030390550 10.67 3.0 3.3 3, 8Apr. 15 21 43 788 Hohensteina 0.05 HSOY 543458328 10.44 6.8 3.6 3 22 2 30 1760 Sandra 0.02 TYC 6285-02653-1 10.94 4.6 5.8 3May 4 1 53 314 Rosalia 0.03 TYC 4977-00665-1 10.97 4.1 3.8 3 8 21 50 252 Clementina 0.04 TYC 5618-00689-1 9.10 5.4 4.7 3, 6Jun. 14 3 49 785 Zwetana 0.04 HIP 107134 7.77 7.8 6.0 3 8 21 48 1436 Salonta 0.04 HSOY 455234677 10.69 7.8 4.5 3,5,6Jul. 11 22 19 835 Olivia 0.02 TYC 6764-00901-1 10.69 11.8 6.1 3 27 3 18 445 Edna 0.07 TYC 5756-01902-1 9.58 6.5 3.7 3Aug. 3 21 42 2326 Tololo 0.03 HSOY 449527179 10.85 3.8 4.3 3Sep. 8 0 36 654 Zelinda 0.11 HIP 7594 8.25 19.0 4.4 3 10 4 55 539 Pamina 0.04 HSOY 528905779 10.76 3.3 3.4 3 14 4 28 524 Fidelio 0.05 TYC 2419-00637-1 10.45 3.2 4.2 3 18 17 51 357 Ninina 0.06 HSOY 094319938 10.10 15.1 4.1 3 29 2 12 3036 Krat 0.03 TYC 1809-00776-1 9.27 4.4 5.6 3 29 20 09 465 Alekto 0.04 UCAC4-540-003316 9.39 5.7 5.9 3,5,7Oct. 7 22 21 501 Urhixidur 0.05 TYC 7458-00695-1 10.41 6.7 3.4 3 16 17 12 973 Aralia 0.04 TYC 1752-01421-1 9.93 4.3 4.0 3 19 6 03 1191 Alfaterna 0.02 HSOY 541218702 8.48 4.4 7.5 3 26 18 42 1583 Antilochus 0.03 TYC 1076-00329-1 10.98 6.0 5.4 3 31 4 32 164 Eva 0.08 TYC 1920-01735-1 9.40 9.4 3.7 3Nov. 9 19 08 702 Alauda 0.08 TYC 6300-00233-1 9.62 6.8 3.7 3 15 16 32 407 Arachne 0.07 HSOY 457313493 10.34 10.5 3.1 3 25 19 04 140 Siwa 0.07 TYC 6364-00547-1 10.77 4.0 2.4 3Dec. 8 21 33 804 Hispania 0.10 TYC 3360-00271-1 9.07 10.8 3.2 3, 7 10 20 36 479 Caprera 0.08 HIP 33753 7.74 10.8 5.0 3, 5 15 1 02 1212 Francette 0.05 TYC 0793-01335-1 10.63 15.0 4.1 3, 5 16 2 41 1191 Alfaterna 0.03 HSOY 538058177 7.53 3.8 7.4 3, 5 18 4 22 344 Desiderata 0.08 TYC 2910-00235-1 10.88 8.0 2.2 1, 3 20 5 33 136 Austria 0.03 TYC 4913-00903-1 10.75 4.9 3.6 3 24 22 38 524 Fidelio 0.07 TYC 2430-00580-1 9.87 7.1 3.1 3 28 4 47 111 Ate 0.09 TYC 4942-00693-1 10.60 8.7 2.2 3

ASTEROID OCCULTATIONSREGIONAL PREDICTIONS

Minor Planet Diam Max. Mag.Date Time No. Name (IRAS) Star ID V Dur. drop RoV2018 h m " sec.

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BAA Handbook 2018 Asteroids 53

Jan. 3 0 55 1998WV31 0 HSOY 523706083 12.74 6.2 10.7 3Mar. 5 15 48 50000 Quaoar 0.04 HSOY 086403058 14.71 87.4 4.2 8 10 10 21 19521 Chaos 0.01 HSOY 530244775 14.93 104.8 6.3 7 16 11 04 32532 Thereus 0.01 HSOY 517692551 14.91 4.6 5.5 7Apr. 7 20 50 28978 Ixion 0.03 HSOY 030022806 14.93 115.3 4.8 8 14 6 33 38628 Huya 0.02 HSOY 050044678 14.34 26.7 5.3 1May 21 9 06 10199 Chariklo 0.02 HSOY 074732693 14.41 19.9 4.4 1 30 12 03 10199 Chariklo 0.02 HSOY 074732759 14.86 15.8 3.9 8Jun. 6 16 48 10370 Hylonome 0.01 HSOY 087639972 14.96 5.1 6.9 8 12 8 32 10370 Hylonome 0.01 HSOY 087636189 13.75 4.8 8.1 2 19 19 19 10199 Chariklo 0.02 HSOY 073936961 14.81 11.8 3.9 7 26 15 20 134340 Pluto 0.10 HSOY 093262527 13.11 102.9 2.0 7Jul. 5 10 11 10199 Chariklo 0.02 HSOY 073941835 14.76 11.0 3.8 1 8 5 28 50000 Quaoar 0.04 HSOY 086360429 14.60 52.8 4.2 1,2 13 11 16 55576 Amycus 0.01 HSOY 073452846 14.88 5.1 6.1 8 17 22 43 10199 Chariklo 0.02 HSOY 073896574 13.74 11.1 4.9 2,4 18 9 11 55576 Amycus 0.01 HSOY 073449075 14.87 5.2 6.1 1Aug. 15 5 33 134340 Pluto 0.10 HSOY 092576413 12.91 122.9 2.2 1 28 15 34 60558 Echeclus 0.01 HSOY 522957646 14.14 4.8 5.0 7Sep. 2 18 00 50000 Quaoar 0.04 HSOY 048778362 12.57 198.6 6.3 4Oct. 27 8 40 10370 Hylonome 0.01 HSOY 087315782 14.14 5.4 8.0 7

MAJOR PLANET PREDICTIONS

ASTEROID OCCULTATIONSTNO GLOBAL PREDICTIONS

Minor Planet Diam Max. Mag.Date Time No. Name (IRAS) Star ID V Dur. drop RoV2018 h m " sec.

Planet Max. Date Time Name Diam Star ID V Dur. RoV2018 h m " sec. Jan. 24 9 03 Mars 5.37 HIP 77165 7.56 210 1Feb. 1 3 17 Jupiter 35.83 HIP 74669 9.64 8228 3,4,5Apr. 22 16 33 Mars 10.24 TYC 6875-01075-1 9.71 496 7May 16 8 48 Mars 12.95 HIP 99337 9.77 790 1,2Jun. 29 2 41 Mars 20.52 HSOY 078342902 9.96 6203 2,3,4Jul. 5 5 51 Saturn 18.27 TYC 6277-00323-1 9.94 6036 1,2 12 3 08 Saturn 18.22 UCAC4-338-136752 9.29 6255 1,2 29 12 35 Jupiter 38.13 HIP 72182 8.80 16473 6,7,8Aug. 8 4 16 Jupiter 37.07 HIP 72417 8.92 10901 1 12 21 04 Jupiter 36.57 TYC 6155-00408-1 9.70 9359 3,4Oct. 9 22 36 Mars 14.53 TYC 6356-01055-1 9.81 759 4Nov. 17 16 06 Mars 10.32 TYC 5809-00005-1 9.44 401 3,5Dec. 12 23 28 Mars 8.49 TYC 5249-00129-1 9.71 309 2 21 12 09 Venus 30.04 HIP 72373 6.45 824 1

Using the tablesIn the table of predictions : Time = UT of closest geocentric approach. Region of Visibility codes (RoV): 1 = North and Central America 2 = South America 3 = Europe, N. Africa and the Middle East 4 = South Africa 5 = Russia 6 = Pakistan, India, and SE Asia

7 = Japan, China and Taiwan 8 = Australia and New Zealand

Where diameters are not listed in the IRAS catalogue, an assumed value of A, the geometric albedo, has been used to calculate a value for the asteroid diameter. Predictions computed by Edwin Goffin. Track details are available from the Flemish Astronomical Association ftp site:

http://bedekkingen.vvs.be/predictions/Asteroids2018

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54 Asteroids BAA Handbook 2018

ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES

LIGHTCURVE OPPORTUNITIES

Based on an analysis of both numbered and unnumbered objects in the Minor Planet Center MPCORB database by Brian D. Warner.

Asteroids are listed which at opposition reach magnitude 14.5 or brighter, and for which the rotation period is very uncertain or unknown.Where a 'U' code is given as '1' or ‘1+’, the values given are based on fragmentary lightcurves and are likely to be incorrect.

Period/amplitude data are taken from the list maintained by Brian D. Warner, Alan W. Harris of the Space Sci-ence Institute and Petr Pravec of the Astronomical Institute, Ondrejov, Czech Republic, at:

http://www.minorplanet.info/lightcurvedatabase.html

Asteroid Opposition Amplitude Number Name Date V Δ Dec. U Period of Magnitude Variation m d au ° Code h

7319 Leona 01 15.8 14.4 1.990 +6 1 9.6 0.03–0.10957 Camelia 02 03.1 13.9 1.791 –5 1+ 150. 0.3276033 2002 AJ129* 02 06.1 12.6 0.036 +6 2014 SR339* 02 09.1 14.2 0.055 +10 0.692776 Baikal 02 10.9 14.5 0.973 +8 0.04 1903 Adzhimushkaj 02 25.3 14.5 1.897 +15 496 Gryphia 04 23.7 13.9 1.231 –12 1 18. 0.05444193 2005 SE71* 04 28.8 13.6 0.063 +9 1032 Pafuri 04 30.2 13.8 1.793 –6 1 >24. 0.15–0.3821 Fanny 05 06.0 14.1 1.192 –14 1 5.44 0.01 3877 Braes 05 12.9 14.4 1.262 –19 431760 2008 HE 05 21.5 14.0 1.126 +20 795 Fini 06 18.6 13.8 1.662 –53 1+ 9.292 0.02–0.06896 Sphinx 06 19.9 13.1 0.903 –19 1 26.27 0.081097 Vicia 06 30.1 13.3 0.923 –21 1 26.5 0.08 4262 DeVorkin 07 11.5 14.0 0.813 –16 1773 Rumpelstilz 07 16.4 14.2 1.203 –27 1803 Zwicky 07 26.0 14.5 1.067 -42 1 27.1 0.084226 Damiaan 08 08.3 14.0 1.188 –7 1 24. 0.057305 Ossakajusto 08 09.5 14.1 1.156 –15

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BAA Handbook 2018 Asteroids 55

cont'd Asteroid Opposition Amplitude Number Name Date V Δ Dec. U Period of Magnitude Variation m d au ° Code h

2015 FP118* 09 07.0 14.5 0.037 +59 831 Stateira** 09 20.3 14.5 0.962 –1 1 >4. 0.051539 Borrelly 09 21.6 14.4 1.620 –2 1006 Lagrangea 09 25.5 13.6 1.077 +18 1 32.79 0.171458 Mineura 10 05.6 14.5 1.552 +1 1 36 0.04 1236 Thais 10 10.3 13.6 0.885 –8 1 >72. 0.082056 Nancy 10 10.4 13.8 0.913 +10 1 >15. 0.081707 Chantal 10 14.1 13.8 0.875 +10 1 >10. 0.26582 Flagsymphony** 10 19.8 14.4 1.026 +10 1302 Werra 11 03.1 14.4 1.692 +12 0.1 1385 Gelria 11 07.4 14.0 1.497 +6 0.361475 Yalta 11 17.2 14.5 0.973 +14 1965 van de Kamp 11 27.6 14.5 1.309 +20 1 >36. 0.52678 Aavasaksa 12 04.5 14.4 1.098 +24 1 >24. 0.4

* Near-Earth asteroid, when brightest, **Low phase angle target

ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES

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56 Asteroids BAA Handbook 2018

ASTEROIDS: FAVOURABLE OBSERVING OPPORTUNITIES

OPPORTUNITIES AT LOW PHASE ANGLE AND AT OPPOSITION

Asteroids have been selected on the following criteria: V≤14.5, Phase Angle ≤0.20°

Asteroid Opposition Minimum Maximum Number Name Date Phase Angle V Dec. Period Change in Magnitude m d ° ° h

2131 Mayall 01 26.3 0.03 14.4 +19 2.568 0.09 11 Parthenope 01 26.7 0.04 9.9 +19 13.720 0.12 1068 Nofretete 02 05.2 0.13 14.4 +16 6.15 0.04 301 Bavaria 02 09.0 0.11 13.9 +15 12.253 0.31 551 Ortrud 02 10.1 0.15 13.1 +15 13.05 0.18 934 Thuringia 02 15.7 0.16 13.9 +12 8.166 0.66 149 Medusa 02 23.0 0.08 12.9 +10 26.023 0.56 693 Zerbinetta 03 14.1 0.19 13.5 +2 11.475 0.29 642 Clara 03 28.9 0.14 13.9 –4 8.231 0.31 74 Galatea 04 10.7 0.09 13.3 –8 17.268 0.16 215 Oenone 04 12.2 0.05 13.1 –8 27.937 0.20 257 Silesia 04 22.8 0.06 14.1 –12 15.710 0.30 713 Luscinia 04 26.2 0.13 14.1 –14 9.914 0.40 1128 Astrid 05 11.1 0.10 14.3 –18 10.228 0.29 1793 Zoya 05 14.0 0.18 14.0 –18 5.753 0.40 1162 Larissa 05 14.2 0.18 14.2 –19 6.516 0.20 570 Kythera 05 19.5 0.17 13.9 –19 8.12 0.20 299 Thora 05 22.4 0.01 14.3 –20 274 0.39 279 Thule 06 03.1 0.01 14.5 –22 23.896 0.10 522 Helga 07 20.0 0.02 13.7 –21 8.129 0.31 831 Stateira 09 20.3 0.09 14.5 –1 >4 0.05 1409 Isko 09 23.3 0.19 14.1 –0 11.643 0.20 734 Benda 09 26.4 0.01 13.8 +1 7.11 0.32 4509 Gorbatskij 09 26.8 0.20 13.5 +2 6.006 0.81 1225 Ariane 10 05.7 0.01 14.4 +5 5.507 0.36 6582 Flagsymphony 10 19.8 0.05 14.4 +10 968 Petunia 10 22.2 0.04 14.0 +11 61.28 0.38 1390 Abastumani 10 22.8 0.03 13.9 +11 17.1 0.15 368 Haidea 11 08.5 0.05 13.7 +17 9.823 0.23 901 Brunsia 12 19.8 0.11 13.9 +23 3.136 0.28

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BAA Handbook 2018 Asteroids 57

NEO CLOSE APPROACHES TO EARTHPrepared from data on the Jet Propulsion Laboratory's Near Earth Object Program website at:

http://neo.jpl.nasa.gov/ca/This lists asteroids predicted to pass within 0.05 au (about 7.5 million km) of the Earth attaining magnitude 19.5 or brighter during 2018 (as of 2017 Mar 26). Especially favourable approaches are shown in bold. Newly-discovered objects may be added to the list available via the JPL NEO site, so do check this for recent updates. The Nominal Miss Distance is given in Lunar Distances (LD) and Astronomical Units (au). The apparent Elongation and Declination are geocentric. Ephemerides should be obtained near the time of observation from the MPC via its Minor Planet and Comet Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.htmlFor your local ephemerides, choose a location or observatory near your site. Note that the positions of some objects may be subject to significant uncertainty.

Object Close Nominal Relative Magnitude Date Elongation Declination Approach Miss Distance Velocity H (brightest) when when when Date* brightest brightest brightest LD** au km s–1 ° °306383 Jan. 22.8 14.32 0.0368 17.40 21.5 17.2 Jan. 20 105 +382002 CB19 Feb. 3 10.30 0.0265 15.61 25.0 18.6 Feb. 6 169 +22276033 Feb. 4.9 10.95 0.0282 34.04 18.7 12.5 Feb. 6 156 +52015 BN509 Feb. 9.8 12.84 0.0330 17.72 20.7 15.3 Feb. 7 139 +542014 EY24 Feb. 27.1 14.74 0.0379 8.02 24.1 19.0 Feb. 25 125 +452010 GD35 Mar 31.1 15.44 0.0397 11.60 24.5 19.5 Apr. 2 132 +422004 FG29 Apr. 2.6 4.10 0.0105 14.95 26.0 18.7 Apr. 2 119 +28363599 Apr. 12.2 19.26 0.0495 24.52 21.0 17.1 Apr. 10 116 +362016 JP Apr. 21.0 12.03 0.0309 12.77 21.2 17.0 Apr. 24 100 +662013 US3 Apr. 29.4 10.07 0.0259 7.69 21.0 14.8 May 1 139 +22002 JR100 Apr. 29.9 10.77 0.0277 7.68 24.3 18.9 May 4 126 +231999 FN19 May 7.6 9.65 0.0248 5.70 22.5 18.3 May 4 78 +722014 JR25 May 9 14.40 0.0370 16.42 23.4 18.4 May 11 129 +11388945 May 9.4 6.48 0.0166 9.02 20.4 12.9 May 7 160 –322016 HP6 May 12 2.29 0.0059 5.62 25.5 14.6 May 12 178 –181999 LK1 May 15.1 13.24 0.0340 10.03 22.0 15.8 May 20 177 –2368347 May 29.1 9.50 0.0244 13.34 19.9 14.8 May 31 106 +352015 DP155 Jun. 11.2 8.97 0.0231 4.42 21.6 15.1 Jun. 14 142 +3467309 Jun. 23.0 17.88 0.0460 13.99 20.0 16.1 Jun. 18 116 +34441987 Jun. 24.5 7.27 0.0187 12.58 21.5 16.2 Jun. 26 100 +482016 NF23 Aug. 29 13.05 0.0335 9.05 22.9 16.3 Aug. 25 177 –141998 SD9 Aug. 29.3 4.22 0.0108 10.70 24.2 17.6 Aug. 30 97 +252015 FP118 Sep. 3.4 12.24 0.0315 9.76 19.3 14.5 Sep. 7 112 +592015 SW6 Sep. 12 8.75 0.0225 10.69 24.6 18.1 Sep. 14 145 –272014 US7 Oct. 17 2.85 0.0073 8.73 26.4 16.9 Oct. 18 169 –12013 UG1 Oct. 18.1 10.41 0.0267 13.42 22.4 16.2 Oct. 20 148 +35475534 Oct. 29.5 7.51 0.0193 18.11 21.2 15.6 Oct. 28 108 +652002 VE68 Nov. 4.9 14.65 0.0376 8.63 20.5 15.1 Nov. 5 134 +472009 WB105 Nov. 25.5 15.15 0.0389 18.88 23.5 17.0 Nov. 25 174 +232008 WD14 Nov. 27 7.42 0.0191 9.30 22.9 16.6 Nov. 28 118 –382001 WO15 Nov. 29 16.18 0.0416 11.88 22.6 17.7 Dec. 2 133 +162013 VX4 Dec. 9 4.11 0.0106 6.62 23.7 19.1 Dec. 13 71 –6163899 Dec. 22.0 7.36 0.0189 6.24 17.3 13.1 Dec. 16 79 +45418849 Dec. 23.5 16.55 0.0425 17.63 20.7 15.4 Dec. 24 140 +3* Dates are quoted to the nearest day if uncertainty in close approach date is greater than ±0.2 day** Lunar Distance: 1.0 LD = 3.844 x 105 km or 0.00257 AU.

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58 Jupiter BAA Handbook 2018

JUPITER Opposition: May 9 Conjunction: November 26

2018 RA Dec. Mag Equat Diam.

Polar Diam.

DE Δ h m º ' " " º au

Jan. 2 15 0.5 –15 59 –1.8 33.2 31.1 –3.1 5.93112 15 6.8 –16 24 –1.9 34.0 31.8 –3.2 5.79122 15 12.3 –16 45 –1.9 35.0 32.7 –3.2 5.639

Feb. 1 15 16.9 –17 01 –2.0 36.0 33.6 –3.2 5.48111 15 20.6 –17 14 –2.1 37.1 34.7 –3.3 5.318

21 15 23.1 –17 22 –2.1 38.2 35.8 –3.3 5.156Mar. 3 15 24.4 –17 25 –2.2 39.4 36.9 –3.3 5.000

13 15 24.5 –17 23 –2.2 40.6 38.0 –3.4 4.85223 15 23.2 –17 17 –2.3 41.8 39.1 –3.4 4.719

Apr. 2 15 20.8 –17 07 –2.4 42.8 40.1 –3.4 4.604

12 15 17.3 –16 53 –2.4 43.7 40.9 –3.4 4.51222 15 13.0 –16 36 –2.4 44.3 41.5 –3.4 4.446

May 2 15 8.1 –16 16 –2.4 44.7 41.8 –3.4 4.40812 15 3.0 –15 56 –2.5 44.8 41.9 –3.4 4.40122 14 58.1 –15 37 –2.5 44.6 41.7 –3.3 4.423

Jun. 1 14 53.6 –15 19 –2.4 44.1 41.2 –3.3 4.47411 14 49.8 –15 05 –2.4 43.3 40.5 –3.2 4.55221 14 47.0 –14 55 –2.3 42.4 39.6 –3.2 4.652

Jul. 1 14 45.4 –14 50 –2.3 41.3 38.6 –3.1 4.77211 14 44.9 –14 50 –2.2 40.2 37.6 –3.1 4.906

21 14 45.6 –14 56 –2.2 39.0 36.5 –3.0 5.05031 14 47.4 –15 07 –2.1 37.9 35.4 –3.0 5.201

Aug. 10 14 50.4 –15 23 –2.1 36.8 34.4 –3.0 5.35520 14 54.4 –15 43 –2.0 35.8 33.5 –3.0 5.50730 14 59.3 –16 06 –1.9 34.9 32.6 –2.9 5.654

Sep. 9 15 5.0 –16 32 –1.9 34.0 31.8 –2.9 5.79319 15 11.5 –17 00 –1.8 33.3 31.1 –2.9 5.92129 15 18.7 –17 30 –1.8 32.7 30.6 –2.9 6.036

Oct. 9 15 26.5 –18 00 –1.8 32.1 30.1 –2.9 6.13519 15 34.7 –18 31 –1.8 31.7 29.7 –2.9 6.217

29 15 43.4 –19 01 –1.7 31.4 29.4 –2.9 6.280Nov. 8 15 52.3 –19 30 –1.7 31.2 29.2 –2.9 6.323

18 16 1.5 –19 58 –1.7 31.1 29.1 –2.9 6.34528 16 10.8 –20 24 –1.7 31.1 29.1 –2.9 6.345

Dec. 8 16 20.2 –20 48 –1.7 31.2 29.2 –2.9 6.324

18 16 29.5 –21 10 –1.7 31.4 29.4 –2.9 6.28028 16 38.7 –21 29 –1.7 31.7 29.7 –2.9 6.21738 16 47.6 –21 46 –1.8 32.1 30.1 –2.8 6.133

Description of the headings in the table can be found on page 20.

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BAA Handbook 2018 Jupiter 59

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM I

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.º º º º º º º º º º º º

1 222.7 75.6 177.2 35.0 96.1 314.5 12.1 224.3 73.6 123.8 331.2 21.32 20.5 233.5 335.2 193.0 254.1 112.5 170.0 22.0 231.3 281.5 128.8 179.03 178.3 31.4 133.1 351.0 52.2 270.4 327.9 179.8 29.0 79.1 286.5 336.64 336.1 189.3 291.1 149.0 210.2 68.4 125.7 337.5 186.7 236.8 84.2 134.35 133.9 347.1 89.1 307.1 8.2 226.4 283.6 135.3 344.4 34.4 241.8 292.0

6 291.7 145.0 247.0 105.1 166.3 24.3 81.4 293.0 142.1 192.1 39.5 89.77 89.5 302.9 45.0 263.1 324.3 182.3 239.3 90.8 299.8 349.8 197.1 247.48 247.3 100.8 203.0 61.2 122.3 340.2 37.1 248.5 97.4 147.4 354.8 45.19 45.2 258.7 0.9 219.2 280.4 138.2 194.9 46.3 255.1 305.1 152.5 202.810 203.0 56.6 158.9 17.2 78.4 296.1 352.8 204.0 52.8 102.7 310.1 0.5

11 0.8 214.5 316.9 175.3 236.4 94.1 150.6 1.7 210.5 260.4 107.8 158.212 158.6 12.4 114.9 333.3 34.5 252.0 308.4 159.5 8.1 58.0 265.5 315.913 316.4 170.3 272.9 131.4 192.5 49.9 106.3 317.2 165.8 215.7 63.1 113.614 114.3 328.2 70.8 289.4 350.5 207.9 264.1 114.9 323.5 13.4 220.8 271.315 272.1 126.2 228.8 87.4 148.5 5.8 61.9 272.6 121.2 171.0 18.5 69.0

16 69.9 284.1 26.8 245.5 306.5 163.7 219.7 70.4 278.8 328.7 176.1 226.717 227.8 82.0 184.8 43.5 104.6 321.7 17.5 228.1 76.5 126.3 333.8 24.418 25.6 239.9 342.8 201.6 262.6 119.6 175.3 25.8 234.2 284.0 131.5 182.119 183.4 37.8 140.8 359.6 60.6 277.5 333.1 183.5 31.8 81.6 289.1 339.820 341.3 195.8 298.8 157.6 218.6 75.4 130.9 341.2 189.5 239.3 86.8 137.5

21 139.1 353.7 96.8 315.7 16.6 233.3 288.7 138.9 347.2 36.9 244.5 295.222 297.0 151.6 254.8 113.7 174.6 31.2 86.5 296.6 144.8 194.6 42.2 92.923 94.8 309.6 52.8 271.8 332.6 189.1 244.3 94.4 302.5 352.3 199.8 250.624 252.7 107.5 210.8 69.8 130.6 347.0 42.1 252.1 100.2 149.9 357.5 48.425 50.5 265.4 8.8 227.8 288.6 144.9 199.9 49.8 257.8 307.6 155.2 206.1

26 208.4 63.4 166.9 25.9 86.6 302.8 357.6 207.5 55.5 105.2 312.9 3.827 6.3 221.3 324.9 183.9 244.6 100.6 155.4 5.2 213.2 262.9 110.5 161.528 164.1 19.3 122.9 342.0 42.6 258.5 313.2 162.9 10.8 60.5 268.2 319.229 322.0 280.9 140.0 200.6 56.4 111.0 320.6 168.5 218.2 65.9 117.030 119.9 78.9 298.1 358.5 214.3 268.7 118.3 326.1 15.9 223.6 274.731 277.7 236.9 156.5 66.5 275.9 173.5 72.4

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h º h º º m º m m º 1 36.58 7 256.05 10 6.10 1 0.61 6 3.66 2 73.16 8 292.63 20 12.19 2 1.22 7 4.27 3 109.74 9 329.21 30 18.29 3 1.83 8 4.88 4 146.32 10 365.79 40 24.39 4 2.44 9 5.49 5 182.90 11 402.37 50 30.48 5 3.05 10 6.10 6 219.48 12 438.95 60 36.58System I applies to all objects situated on or between the north component of the South Equatorial Belt and the south component of the North Equatorial Belt.

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60 Jupiter BAA Handbook 2018

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM II

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.º º º º º º º º º º º º

1 75.7 52.1 300.0 281.2 113.4 95.3 284.1 259.7 232.6 53.8 24.7 205.92 225.9 202.3 90.4 71.6 263.9 245.7 74.3 49.8 22.6 203.9 174.7 355.93 16.1 352.6 240.7 222.0 54.3 36.0 224.5 199.9 172.7 353.9 324.8 146.04 166.2 142.8 31.0 12.4 204.7 186.3 14.8 350.1 322.7 143.9 114.8 296.15 316.4 293.1 181.4 162.8 355.1 336.7 165.0 140.2 112.8 294.0 264.8 86.1

6 106.6 83.3 331.7 313.2 145.5 127.0 315.2 290.3 262.8 84.0 54.8 236.27 256.8 233.6 122.0 103.6 295.9 277.3 105.4 80.4 52.9 234.0 204.9 26.28 46.9 23.9 272.4 254.0 86.3 67.7 255.6 230.5 203.0 24.0 354.9 176.39 197.1 174.1 62.7 44.4 236.7 218.0 45.8 20.6 353.0 174.1 144.9 326.410 347.3 324.4 213.1 194.8 27.1 8.3 196.0 170.8 143.0 324.1 295.0 116.4

11 137.5 114.7 3.4 345.2 177.5 158.6 346.2 320.9 293.1 114.1 85.0 266.512 287.7 265.0 153.8 135.6 327.9 308.9 136.4 111.0 83.1 264.1 235.0 56.613 77.9 55.2 304.1 286.0 118.3 99.2 286.6 261.1 233.2 54.2 25.1 206.614 228.1 205.5 94.5 76.5 268.7 249.5 76.8 51.2 23.2 204.2 175.1 356.715 18.3 355.8 244.8 226.9 59.1 39.8 227.0 201.3 173.3 354.2 325.2 146.8

16 168.5 146.1 35.2 17.3 209.4 190.1 17.2 351.3 323.3 144.3 115.2 296.817 318.7 296.4 185.5 167.7 359.8 340.4 167.4 141.4 113.4 294.3 265.2 86.918 108.9 86.7 335.9 318.1 150.2 130.7 317.6 291.5 263.4 84.3 55.3 237.019 259.1 237.0 126.3 108.5 300.6 281.0 107.7 81.6 53.4 234.3 205.3 27.120 49.3 27.3 276.6 258.9 91.0 71.3 257.9 231.7 203.5 24.4 355.4 177.2

21 199.5 177.6 67.0 49.3 241.4 221.5 48.1 21.8 353.5 174.4 145.4 327.222 349.8 327.9 217.4 199.7 31.7 11.8 198.2 171.9 143.5 324.4 295.4 117.323 140.0 118.2 7.8 350.2 182.1 162.1 348.4 321.9 293.6 114.4 85.5 267.424 290.2 268.5 158.1 140.6 332.5 312.3 138.5 112.0 83.6 264.5 235.5 57.525 80.4 58.8 308.5 291.0 122.8 102.6 288.7 262.1 233.7 54.5 25.6 207.6

26 230.7 209.1 98.9 81.4 273.2 252.8 78.8 52.2 23.7 204.5 175.6 357.727 20.9 359.4 249.3 231.8 63.6 43.1 229.0 202.2 173.7 354.5 325.7 147.728 171.1 149.7 39.7 22.2 213.9 193.3 19.1 352.3 323.8 144.6 115.7 297.829 321.4 190.1 172.6 4.3 343.6 169.3 142.4 113.8 294.6 265.8 87.930 111.6 340.4 323.0 154.6 133.8 319.4 292.4 263.8 84.6 55.8 238.0

31 261.8 130.8 305.0 109.6 82.5 234.7 28.1

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º

1 36.26 7 253.83 10 6.04 1 0.60 6 3.63 2 72.52 8 290.09 20 12.09 2 1.21 7 4.23 3 108.78 9 326.35 30 18.13 3 1.81 8 4.83 4 145.05 10 362.61 40 24.17 4 2.42 9 5.44 5 181.31 11 398.87 50 30.22 5 3.02 10 6.04 6 217.57 12 435.14 60 36.26System II applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt.

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BAA Handbook 2018 Jupiter 61

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM III (2009)

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec.º º º º º º º º º º º º

1 266.2 250.8 146.2 135.6 335.8 326.0 162.7 146.5 127.7 316.9 296.0 125.22 56.6 41.3 296.8 286.3 126.5 116.6 313.2 296.9 278.0 107.2 86.3 275.53 207.0 191.8 87.4 77.0 277.2 267.2 103.7 87.3 68.3 257.5 236.6 65.84 357.5 342.3 238.0 227.6 67.8 57.8 254.2 237.7 218.6 47.8 26.9 216.25 147.9 132.9 28.6 18.3 218.5 208.4 44.7 28.1 9.0 198.1 177.2 6.5

6 298.4 283.4 179.2 168.9 9.2 359.0 195.1 178.5 159.3 348.4 327.5 156.87 88.8 73.9 329.8 319.6 159.9 149.6 345.6 328.9 309.6 138.7 117.8 307.18 239.3 224.4 120.4 110.3 310.5 300.1 136.1 119.2 99.9 289.0 268.1 97.59 29.7 15.0 271.0 261.0 101.2 90.7 286.6 269.6 250.2 79.3 58.4 247.810 180.2 165.5 61.6 51.6 251.9 241.3 77.0 60.0 40.5 229.6 208.7 38.1

11 330.6 316.0 212.2 202.3 42.5 31.9 227.5 210.4 190.9 19.9 359.0 188.512 121.1 106.6 2.8 353.0 193.2 182.5 18.0 0.7 341.2 170.2 149.3 338.813 271.5 257.1 153.5 143.6 343.8 333.0 168.4 151.1 131.5 320.4 299.6 129.114 62.0 47.7 304.1 294.3 134.5 123.6 318.9 301.5 281.8 110.7 89.9 279.515 212.5 198.2 94.7 85.0 285.2 274.2 109.3 91.8 72.1 261.0 240.2 69.8

16 2.9 348.8 245.3 235.7 75.8 64.7 259.8 242.2 222.4 51.3 30.5 220.117 153.4 139.3 36.0 26.3 226.5 215.3 50.2 32.5 12.7 201.6 180.8 10.518 303.9 289.9 186.6 177.0 17.1 5.8 200.7 182.9 163.0 351.9 331.1 160.819 94.4 80.4 337.2 327.7 167.8 156.4 351.1 333.3 313.3 142.2 121.4 311.220 244.8 231.0 127.8 118.4 318.4 306.9 141.6 123.6 103.6 292.5 271.7 101.5

21 35.3 21.6 278.5 269.1 109.1 97.5 292.0 274.0 253.9 82.8 62.0 251.922 185.8 172.1 69.1 59.7 259.7 248.0 82.4 64.3 44.2 233.1 212.4 42.223 336.3 322.7 219.8 210.4 50.3 38.5 232.8 214.6 194.5 23.4 2.7 192.624 126.8 113.3 10.4 1.1 201.0 189.1 23.3 5.0 344.8 173.7 153.0 342.925 277.3 263.9 161.1 151.8 351.6 339.6 173.7 155.3 135.1 324.0 303.3 133.3

26 67.8 54.4 311.7 302.4 142.2 130.1 324.1 305.7 285.4 114.2 93.6 283.627 218.3 205.0 102.4 93.1 292.9 280.6 114.5 96.0 75.7 264.5 243.9 74.028 8.8 355.6 253.0 243.8 83.5 71.2 264.9 246.3 226.0 54.8 34.2 224.329 159.3 43.7 34.5 234.1 221.7 55.3 36.7 16.3 205.1 184.6 14.730 309.8 194.3 185.2 24.7 12.2 205.7 187.0 166.6 355.4 334.9 165.0

31 100.3 345.0 175.3 356.1 337.3 145.7 315.4

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 36.27 7 253.91 10 6.05 1 0.60 6 3.63 2 72.54 8 290.18 20 12.09 2 1.21 7 4.23 3 108.82 9 326.45 30 18.14 3 1.81 8 4.84 4 145.09 10 362.72 40 24.18 4 2.42 9 5.44 5 181.36 11 399.00 50 30.23 5 3.02 10 6.05 6 217.63 12 435.27 60 36.27System III applies to the origin of radio emissions from the planet. See page 62 for a description.

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62 Satellites of Jupiter BAA Handbook 2018

SATELLITES OF JUPITER

The satellites move from east to west across the face of the planet, and from west to east behind it. After conjunction with the Sun and before opposition, the shadow of Jupiter falls to the west, eclipse precedes occultation, and shadow–transit precedes transit. After opposition, the order of phenomena is reversed, occultation preceding eclipse and transit preceding shadow–transit.

Both phases of eclipse (EcD and EcR) and of occultation (OcD and OcR) of satellites III and IV may be seen if not too near opposition. Satellite I is much closer to the planet, and eclipse and occultation merge into one, OcD being followed by EcR after opposition and before conjunction, while EcD is followed by OcR after conjunction and before opposition. Satellite II normally behaves in the same manner but on rare occasions the separate phenomena of II may be observed. This happens when the planet is near quadrature and is tilted at almost the maximum amount.

On a few occasions all three of the inner satellites may be involved simultaneously in these phenomena. The motions of these three satellites are related in such a way that it is impossible for all three to undergo the same phenomenon at the same time.

The Institut de Mécanique Céleste et de Calcul des Ephémérides supplies event timings in Terrestrial Time (TT). These have been converted to Universal Time (UT), closely, by subtracting one minute (see tables on p.67–76), since ΔT is just over one minute now. The times of phenomena are given for the centre of the satellite. The light of the satellite will therefore begin to fade before the times given here, and observation should commence several minutes before the predicted times.

Charts are included for all 12 months of the year, even though Jupiter will be in conjunction with the Sun on November 26, and therefore not observable for a few weeks either side of this date.

For all charts the satellites are labelled: I Io II Europa III Ganymede IV Callisto

LONGITUDE OF CENTRAL MERIDIAN OF JUPITERSYSTEM III – DEFINITION

Radio radiation from Jupiter at around 20MHz was discovered in 1955. It varies with the rotation of the planet and this is known as "System III". It is of interest because it indicates rotation beneath the cloud cover. Radio radiation emanates from the magnetosphere of Jupiter, and the rotation is due to the fact that the magnetic poles are not situated exactly at the poles of rotation. (The position of the satellite Io and the DE value are also significant for predicting "radio storms" from Jupiter.) In 1976 the IAU adopted a rotation for System III of 870.536 degrees per day. More recent work suggested an improvement to 870.536642, adopted in 2000 and used in recent BAA Handbooks. However subsequent analysis of data from Galileo gives a different value, consistent with 870.536 and its implied accuracy but not with 870.536642. The IAU provisionally recommends that 870.536 be used.

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BAA Handbook 2018 Satellites of Jupiter 63

SAT

EL

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OF

JU

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201

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64 Satellites of Jupiter BAA Handbook 2018

SAT

EL

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OF

JU

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201

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SATE

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May

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BAA Handbook 2018 Satellites of Jupiter 65

SAT

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Aug

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66 Satellites of Jupiter BAA Handbook 2018

SAT

EL

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OF

JU

PIT

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201

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BAA Handbook 2018 Satellites of Jupiter 67

ECLIPSES, OCCULTATIONS AND TRANSITSThe times are for mid–phenomena, i.e. for eclipses, the planet’s shadow bisecting the satellite; for other events, Jupiter’s limb bisecting the satellite or the satellite shadow.

Abbreviations: OcD and OcR occultation disappearance and reappearance EcD and EcR eclipse disappearance and reappearance TrI and TrE transit ingress and egress ShI and ShE shadow–transit ingress and egress

January

Occultations and Eclipses Date Sat. EcD EcR OcD OcR 1 III 12 00 13 52 16 05 17 51 1 I 14 07 17 17 3 II 07 52 12 14 3 I 08 35 11 46 5 I 03 04 06 15 6/7 II 21 10 01 36 6/7 I 21 32 00 44 8 III 15 57 17 49 20 21 22 04 8 I 16 00 19 14 10 I 10 28 13 43 10 II 10 28 14 58 12 I 04 57 08 12 13/14 I 23 25 02 41 13/14 II 23 46 02 04 02 04 04 20 15 I 17 53 21 10 15/16 III 19 54 21 45 00 34 02 13 17 I 12 21 15 39 17 II 13 03 15 21 15 25 17 40 19 I 06 49 10 08 21 I 01 18 04 37 21 II 02 22 04 39 04 47 07 01 22 I 19 46 23 06 22/23 III 23 51 01 42 04 45 06 21 24 I 14 14 17 34 24 II 15 39 17 57 18 07 20 21 26 I 08 42 12 03 28 I 03 10 06 32 28 II 04 58 07 15 07 28 09 41 29/30 I 21 39 01 00 30 III 03 48 05 39 08 52 10 24 31 I 16 07 19 29 31 II 18 15 20 32 20 47 23 00

January Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 0 I 16 53 19 03 17 52 20 02 1 II 13 17 15 33 15 15 17 30 2 I 11 21 13 31 12 21 14 31 4 I 05 50 07 59 06 51 09 01 5 III 01 46 03 37 06 01 07 44 5 II 02 34 04 49 04 36 06 50 6 I 00 18 02 28 01 20 03 30 7 I 18 46 20 56 19 50 21 59 8 II 15 50 18 06 17 57 20 10 9 I 13 15 15 25 14 19 16 29 11 I 07 43 09 53 08 49 10 58 12 II 05 07 07 22 07 17 09 30 12 III 05 45 07 35 10 17 11 56 13 I 02 12 04 21 03 18 05 27 14 I 20 40 22 50 21 47 23 56 15 II 18 23 20 38 20 37 22 50 16 I 15 08 17 18 16 16 18 26 18 I 09 37 11 47 10 46 12 55 19 II 07 40 09 55 09 56 12 09 19 III 09 43 11 32 14 30 16 05 20 I 04 05 06 15 05 15 07 24 21/22 I 22 34 00 43 23 44 01 53 22/23 II 20 56 23 11 23 16 01 28 23 I 17 02 19 12 18 13 20 22 25 I 11 30 13 40 12 42 14 51 26 II 10 12 12 27 12 34 14 46 26 III 13 41 15 29 18 40 20 11 27 I 05 59 08 08 07 11 09 19 29 I 00 27 02 37 01 39 03 48 29/30 II 23 29 01 44 01 53 04 05 30 I 18 55 21 05 20 08 22 17

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68 Satellites of Jupiter BAA Handbook 2018

ECLIPSES, OCCULTATIONS AND TRANSITSFebruary Occultations and Eclipses Date Sat. EcD EcR OcD OcR

2 I 10 35 13 58 4 I 05 03 08 26 4 II 07 33 09 51 10 06 12 20 5/6 I 23 31 02 54 6 III 07 47 09 36 12 57 14 25 7 I 18 00 21 23 7/8 II 20 51 23 08 23 25 01 37 9 I 12 28 15 51 11 I 06 56 10 19 11 II 10 09 12 26 12 43 14 56 13 I 01 24 04 47 13 III 11 44 13 33 16 57 18 21 14 I 19 52 23 16 14/15 II 23 26 01 44 02 01 04 13 16 I 14 21 17 44 18 I 08 49 12 12 18 II 12 45 15 02 15 18 17 30 20 I 03 17 06 40 20 III 15 41 17 30 20 52 22 13 21/22 I 21 45 01 07 22 II 02 02 04 19 04 34 06 46 23 I 16 13 19 35 25 I 10 42 14 03 25 II 15 20 17 37 17 51 20 02 27 I 05 10 08 31 27/28 III 19 38 21 27 00 43 02 01 28/1 I 23 38 02 58

February Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

1 I 13 24 15 33 14 37 16 46 2 II 12 45 15 00 15 11 17 22 2/ 3 III 17 38 19 26 22 45 00 13 3 I 07 52 10 02 09 06 11 14 5 I 02 21 04 30 03 34 05 43 6 II 02 02 04 16 04 29 06 39 6/ 7 I 20 49 22 58 22 03 00 11 8 I 15 17 17 27 16 31 18 40 9 II 15 18 17 33 17 46 19 56 9/10 III 21 36 23 23 02 47 04 11 10 I 09 46 11 55 11 00 13 08 12 I 04 14 06 23 05 28 07 37 13 II 04 35 06 49 07 02 09 13 13/14 I 22 42 00 52 23 56 02 05 15 I 17 11 19 20 18 25 20 33 16 II 17 51 20 06 20 19 22 29 17 III 01 33 03 20 06 46 08 06 17 I 11 39 13 48 12 53 15 01 19 I 06 07 08 17 07 21 09 29 20 II 07 07 09 22 09 34 11 44 21 I 00 36 02 45 01 49 03 57 22 I 19 04 21 14 20 17 22 25 23/24 II 20 24 22 39 22 49 00 59 24 III 05 31 07 17 10 39 11 56 24 I 13 32 15 42 14 45 16 53 26 I 08 01 10 10 09 13 11 21 27 II 09 40 11 55 12 04 14 13 28 I 02 29 04 38 03 41 05 49

March Occultations and Eclipses Date Sat. EcD EcR OcD OcR 1 II 04 38 06 54 07 06 09 16 2 I 18 06 21 26 4 I 12 35 15 53 4 II 17 56 20 12 20 21 22 31 6 I 07 03 10 21 6/7 III 23 35 01 23 04 30 05 44 8 I 01 31 04 48 8 II 07 13 09 30 09 35 11 45 9 I 19 59 23 15 11 I 14 27 17 43

March Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 1/ 2 I 20 57 23 07 22 08 00 16 2/ 3 II 22 57 01 12 01 18 03 27 3 III 09 29 11 15 14 29 15 42 3 I 15 26 17 35 16 36 18 44 5 I 09 54 12 04 11 04 13 12 6 II 12 13 14 28 14 32 16 41 7 I 04 22 06 32 05 31 07 39 8/ 9 I 22 51 01 00 23 59 02 07 10 II 01 30 03 45 03 45 05 54 10 III 13 27 15 13 18 14 19 24

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ECLIPSES, OCCULTATIONS AND TRANSITS

March cont'd Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

10 I 17 19 19 29 18 26 20 34 12 I 11 47 13 57 12 53 15 01 13 II 14 47 17 01 16 58 19 06 14 I 06 16 08 25 07 20 09 28 16 I 00 44 02 54 01 48 03 56 17 II 04 03 06 18 06 10 08 18 17 III 17 25 19 10 21 54 23 01 17 I 19 12 21 22 20 15 22 23 19 I 13 41 15 50 14 42 16 50 20 II 17 20 19 35 19 21 21 30 21 I 08 09 10 19 09 09 11 17 23 I 02 38 04 47 03 36 05 44 24 II 06 37 08 52 08 33 10 41 24/25 I 21 06 23 15 22 02 00 10 24/25 III 21 22 23 07 01 29 02 33 26 I 15 34 17 44 16 29 18 37 27 II 19 54 22 09 21 43 23 51 28 I 10 03 12 12 10 56 13 04 30 I 04 31 06 41 05 23 07 31 31 II 09 11 11 26 10 53 13 01 31/ 1 I 22 59 01 09 23 49 01 57 April Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 1 III 01 19 03 04 04 59 06 02 2 I 17 28 19 37 18 16 20 24 3/ 4 II 22 27 00 43 00 03 02 11 4 I 11 56 14 06 12 42 14 50 6 I 06 24 08 34 07 09 09 17 7 II 11 44 14 00 13 12 15 20 8 I 00 53 03 03 01 35 03 43 8 III 05 17 07 02 08 25 09 27 9 I 19 21 21 31 20 01 22 09 11 II 01 01 03 17 02 21 04 29 11 I 13 49 15 59 14 28 16 36 13 I 08 18 10 28 08 54 11 02 14 II 14 19 16 34 15 29 17 37 15 I 02 46 04 56 03 20 05 28 15 III 09 14 10 59 16 I 21 15 23 25 21 46 23 54

March cont'd Occultations and Eclipses Date Sat. EcD EcR OcD OcR 11/12 II 20 31 22 48 22 49 00 58 13 I 08 56 12 10 14 III 03 32 05 20 08 12 09 23 15 I 03 24 06 37 15 II 09 48 14 11 16/17 I 21 52 01 04 18 I 16 20 19 31 18/19 II 23 06 03 23 20 I 10 49 13 58 21 III 07 30 09 17 11 49 12 57 22 I 05 17 08 25 22 II 12 24 16 35 23/24 I 23 45 02 51 25 I 18 14 21 18 26 II 01 42 05 46 27 I 12 42 15 45 28 III 11 28 13 15 15 23 16 29 29 I 07 10 10 11 29 II 14 59 18 57 31 I 01 38 04 38

April Occultations and Eclipses Date Sat. EcD EcR OcD OcR 1 I 20 07 23 05 2 II 04 17 08 07 3 I 14 35 17 31 4 III 15 26 17 13 18 51 19 56 5 I 09 03 11 57 5 II 17 34 21 16 7 I 03 32 06 24 8/9 I 22 00 00 50 9 II 06 52 10 26 10 I 16 29 19 16 11 III 19 24 21 10 22 15 23 20 12 I 10 57 13 43 12 II 20 10 23 35 14 I 05 25 08 09 15/16 I 23 54 02 35 16 II 09 27 12 43

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ECLIPSES, OCCULTATIONS AND TRANSITS

April cont'd Occultations and Eclipses Date Sat. EcD EcR OcD OcR 17 I 18 22 21 01 18/19 III 23 21 01 08 01 35 02 41 19 I 12 50 15 27 19/20 II 22 45 01 51 21 I 07 19 09 53 23 I 01 47 04 19 23 II 12 02 14 59 24 I 20 16 22 45 26 III 03 19 06 00 26 I 14 44 17 11 27 II 01 20 04 07 28 I 09 13 11 37 30 I 03 41 06 03 30 II 14 38 17 14

May Occultations and Eclipses Date Sat. EcD EcR OcD OcR

1/2 I 22 10 00 29 3 III 07 17 09 18 3 I 16 38 18 55 4 II 03 55 06 22 5 I 11 07 13 21 7 I 05 35 07 47 7 II 17 13 19 29 9 I 00 04 02 14

April cont'd Transits and Shadow Transits Date Sat. ShI ShE TrI TrE 18 II 03 36 05 51 04 37 06 45 18 I 15 43 17 53 16 12 18 20 20 I 10 12 12 21 10 38 12 47 21 II 16 53 19 09 17 45 19 54 22 I 04 40 06 50 05 04 07 13 22 III 13 13 14 58 15 07 16 11 23/24 I 23 08 01 18 23 30 01 39 25 II 06 10 08 26 06 53 09 01 25 I 17 37 19 47 17 56 20 05 27 I 12 05 14 15 12 22 14 31 28 II 19 28 21 43 20 00 22 09 29 I 06 34 08 44 06 48 08 57 29 III 17 11 18 56 18 24 19 30

May Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

1 I 01 02 03 12 01 14 03 23 2 II 08 45 11 01 09 08 11 16 2 I 19 31 21 41 19 40 21 49 4 I 13 59 16 09 14 06 16 15 5/ 6 II 22 03 00 19 22 15 00 24 6 I 08 28 10 38 08 32 10 41 6 III 21 09 22 53 21 39 22 49 8 I 02 56 05 06 02 58 05 07

Jupiter in Opposition to the Sun: 2018 May 9d 1h

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BAA Handbook 2018 Satellites of Jupiter 71

ECLIPSES, OCCULTATIONS AND TRANSITS May cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

10 III 11 15 13 01 10 I 18 30 20 42 11 II 06 26 08 46 12 I 12 56 15 11 14 I 07 22 09 39 14 II 19 34 22 04 16 I 01 48 04 08 17 III 14 38 17 00 17 I 20 14 22 37 18 II 08 41 11 21 19 I 14 40 17 05 21 I 09 06 11 34 21/22 II 21 48 00 39 23 I 03 32 06 02 24 III 17 54 20 59 24/25 I 21 59 00 31 25 II 10 56 13 56 26 I 16 25 19 00 28 I 10 51 13 28 29 II 00 03 03 13 30 I 05 17 07 57 31/1 III 21 11 22 39 23 12 00 58 31/1 I 23 44 02 26

June

Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 II 13 11 16 31 2 I 18 10 20 54 4 I 12 36 15 23 5 II 02 20 05 48 6 I 07 03 09 51 8 I 01 29 04 20 8 III 03 10 04 56 8 II 15 29 19 06 9 I 19 56 22 49 11 I 14 22 17 18 12 II 04 38 08 23 13 I 08 49 11 46 15 I 03 16 06 15

May cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

9 II 11 22 13 31 11 20 13 36 9 I 21 24 23 32 21 25 23 35 11 I 15 50 17 58 15 53 18 03 13 II 00 29 02 39 00 38 02 54 13 I 10 16 12 24 10 22 12 32 14 III 00 53 02 07 01 07 02 52 15 I 04 42 06 50 04 50 07 00 16 II 13 37 15 47 13 56 16 12 16/17 I 23 08 01 16 23 19 01 29 18 I 17 34 19 42 17 47 19 57 20 II 02 44 04 55 03 14 05 30 20 I 12 00 14 08 12 16 14 26 21 III 04 07 05 26 05 05 06 50 22 I 06 26 08 35 06 44 08 54 23 II 15 52 18 03 16 32 18 47 24 I 00 52 03 01 01 13 03 23 25 I 19 18 21 27 19 42 21 51 27 II 05 00 07 11 05 50 08 06 27 I 13 44 15 53 14 10 16 20 28 III 07 23 08 47 09 04 10 48 29 I 08 11 10 19 08 39 10 48 30 II 18 08 20 20 19 08 21 24 31 I 02 37 04 46 03 07 05 17

June Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 I 21 03 23 12 21 36 23 45 3 II 07 17 09 29 08 26 10 42 3 I 15 30 17 38 16 04 18 14 4 III 10 42 12 11 13 02 14 46 5 I 09 56 12 05 10 33 12 42 6/ 7 II 20 26 22 38 21 44 00 00 7 I 04 22 06 31 05 02 07 11 8/ 9 I 22 49 00 58 23 30 01 40 10 II 09 36 11 49 11 03 13 18 10 I 17 16 19 24 17 59 20 08 11 III 14 05 15 38 17 02 18 46 12 I 11 42 13 51 12 27 14 37 13/14 II 22 46 00 59 00 21 02 36

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ECLIPSES, OCCULTATIONS AND TRANSITS

June cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

14 I 06 09 08 18 06 56 09 05 16 I 00 36 02 44 01 25 03 34 17 II 11 56 14 10 13 39 15 55 17 I 19 02 21 11 19 53 22 02 18 III 17 31 19 09 21 00 22 45 19 I 13 29 15 38 14 22 16 31 21 II 01 07 03 21 02 58 05 13 21 I 07 56 10 05 08 50 11 00 23 I 02 23 04 32 03 19 05 28 24 II 14 19 16 34 16 16 18 32 24 I 20 50 22 59 21 48 23 57 25/26 III 21 01 22 43 00 59 02 43 26 I 15 18 17 26 16 16 18 25 28 II 03 31 05 46 05 35 07 50 28 I 09 45 11 54 10 45 12 54 30 I 04 12 06 21 05 14 07 23

June cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

15 III 03 55 05 32 07 09 08 54 15 II 17 47 21 41 16/17 I 21 43 00 44 18 I 16 10 19 12 19 II 06 57 10 58 20 I 10 36 13 41 22 I 05 03 08 10 22 III 07 22 09 04 11 08 12 54 22/23 II 20 08 00 16 23/24 I 23 31 02 39 25 I 17 58 21 08 26 II 09 19 13 33 27 I 12 25 15 36 29 I 06 52 10 05 29 III 10 55 12 41 15 07 16 53 29/30 II 22 31 02 50

July Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 I 01 20 04 34 2 I 19 47 23 03 3 II 11 43 16 08 4 I 14 15 17 31 6 I 08 42 12 00 6 III 14 32 16 22 19 07 20 53 7 II 00 55 05 25 8 I 03 10 06 29 9/10 I 21 38 00 58 10 II 14 09 16 25 16 27 18 43 11 I 16 05 19 27 13 I 10 33 13 55 13/14 III 18 14 20 07 23 06 00 52 14 II 03 22 05 39 05 44 08 00 15 I 05 01 08 24

July Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 II 16 44 18 59 18 54 21 09 1/ 2 I 22 39 00 48 23 42 01 51 3 III 00 35 02 21 04 58 06 42 3 I 17 07 19 16 18 11 20 20 5 II 05 57 08 13 08 12 10 27 5 I 11 34 13 43 12 40 14 48 7 I 06 02 08 11 07 08 09 17 8 II 19 11 21 27 21 31 23 46 9 I 00 29 02 38 01 37 03 46 10 III 04 13 06 03 08 56 10 40 10 I 18 57 21 06 20 06 22 14 12 II 08 26 10 42 10 49 13 04 12 I 13 25 15 34 14 34 16 43 14 I 07 53 10 02 09 03 11 12 15/16 II 21 41 23 58 00 08 02 23

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ECLIPSES, OCCULTATIONS AND TRANSITS

July cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

16/17 I 23 29 02 53 17 II 16 36 18 54 19 02 21 17 18 I 17 57 21 22 20 I 12 25 15 51 20/21 III 22 00 23 56 03 06 04 52 21 II 05 51 08 09 08 19 10 35 22 I 06 54 10 19 24 I 01 22 04 48 24 II 19 07 21 25 21 36 23 52 25 I 19 50 23 17 27 I 14 19 17 46 28 III 01 51 03 49 07 05 08 51 28 II 08 22 10 41 10 54 13 10 29 I 08 47 12 15 31 I 03 16 06 44 31/1 II 21 39 23 57 00 11 02 27

July cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

16 I 02 21 04 29 03 32 05 40 17 III 07 57 09 50 12 55 14 40 17/18 I 20 49 22 57 22 00 00 09 19 II 10 56 13 13 13 27 15 42 19 I 15 17 17 25 16 29 18 37 21 I 09 45 11 54 10 58 13 06 23 II 00 13 02 30 02 46 05 01 23 I 04 13 06 22 05 26 07 35 24 III 11 45 13 40 16 54 18 39 24/25 I 22 41 00 50 23 55 02 03 26 II 13 29 15 47 16 04 18 19 26 I 17 09 19 18 18 24 20 32 28 I 11 38 13 47 12 52 15 01 30 II 02 47 05 05 05 23 07 39 30 I 06 06 08 15 07 21 09 29 31 III 15 39 17 36 20 54 22 39

August Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1/2 I 21 44 01 13 3 I 16 13 19 41 4 III 05 45 07 46 11 04 12 50 4 II 10 55 13 14 13 28 15 44 5 I 10 42 14 10 7 I 05 11 08 39 8 II 00 13 02 32 02 46 05 02 8/9 I 23 40 03 08 10 I 18 09 21 37 11 III 09 45 11 47 15 03 16 50 11 II 13 30 15 49 16 03 18 19 12 I 12 37 16 06 14 I 07 07 10 34 15 II 02 48 05 08 05 20 07 36 16 I 01 36 05 03 17 I 20 05 23 32 18 III 13 48 15 51 19 02 20 50 18 II 16 07 18 26 18 37 20 54 19 I 14 34 18 01

August Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1 I 00 34 02 44 01 50 03 58 2 II 16 05 18 23 18 42 20 57 2 I 19 03 21 12 20 18 22 27 4 I 13 32 15 41 14 47 16 55 6 II 05 23 07 42 08 01 10 16 6 I 08 00 10 09 09 16 11 24 7/ 8 III 19 36 21 35 00 53 02 38 8 I 02 29 04 38 03 44 05 53 9 II 18 42 21 00 21 19 23 35 9/10 I 20 58 23 07 22 13 00 21 11 I 15 26 17 36 16 42 18 50 13 II 08 02 10 20 10 39 12 54 13 I 09 55 12 04 11 10 13 19 14/15 III 23 37 01 38 04 52 06 37 15 I 04 24 06 33 05 39 07 48 16/17 II 21 21 23 40 23 57 02 13 16/17 I 22 53 01 02 00 08 02 16 18 I 17 22 19 31 18 36 20 45 20 II 10 42 13 01 13 16 15 32

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74 Satellites of Jupiter BAA Handbook 2018

ECLIPSES, OCCULTATIONS AND TRANSITS

September Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 I 00 00 03 23 1/2 II 21 25 23 45 23 47 02 03 1/2 III 22 06 00 12 03 02 04 50 2 I 18 29 21 52 4 I 12 59 16 20 5 II 10 46 15 20 6 I 07 29 10 49 8 I 01 59 05 18 9 II 00 06 04 38 9 III 02 19 04 26 07 01 08 50 9 I 20 28 23 47 11 I 14 58 18 16 12 II 13 28 17 55 13 I 09 28 12 44 15 I 03 58 07 13 16 II 02 49 07 12 16 III 06 35 08 42 11 00 12 49 16/17 I 22 28 01 42 18 I 16 58 20 11 19 II 16 11 20 30 20 I 11 28 14 40 22 I 05 58 09 09 23 II 05 33 09 47 23 III 10 53 13 00 14 59 16 48 24 I 00 28 03 37

September Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1/ 2 I 21 16 23 25 22 26 00 34 3 I 15 45 17 55 16 54 19 03 3 II 16 07 18 27 18 31 20 48 5 I 10 15 12 24 11 23 13 32 5 III 12 00 14 04 16 48 18 35 7 I 04 44 06 54 05 52 08 00 7 II 05 29 07 49 07 50 10 06 8/ 9 I 23 14 01 23 00 20 02 29 10 I 17 43 19 53 18 49 20 58 10 II 18 52 21 12 21 09 23 25 12 I 12 13 14 23 13 18 15 26 12 III 16 14 18 19 20 47 22 34 14 I 06 43 08 52 07 46 09 55 14 II 08 14 10 35 10 27 12 44 16 I 01 12 03 22 02 15 04 24 17 I 19 42 21 52 20 43 22 52 17/18 II 21 38 23 58 23 46 02 03 19 I 14 12 16 22 15 12 17 21 19/20 III 20 32 22 37 00 46 02 34 21 I 08 41 10 51 09 41 11 50 21 II 11 01 13 22 13 05 15 21 23 I 03 11 05 21 04 09 06 18 24/25 I 21 41 23 51 22 38 00 47

August cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

21 I 09 03 12 30 22 II 05 26 07 46 07 55 10 11 23 I 03 33 06 59 24/25 I 22 02 01 27 25/26 III 17 56 20 00 23 03 00 50 25 II 18 45 21 05 21 12 23 28 26 I 16 31 19 56 28 I 11 01 14 25 29 II 08 05 10 25 10 29 12 46 30 I 05 30 08 54

August cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

20 I 11 51 14 01 13 05 15 14 22 III 03 41 05 43 08 50 10 36 22 I 06 20 08 30 07 34 09 42 24 II 00 02 02 22 02 35 04 50 24 I 00 49 02 59 02 02 04 11 25 I 19 19 21 28 20 31 22 40 27 II 13 24 15 43 15 54 18 10 27 I 13 48 15 57 15 00 17 08 29 III 07 49 09 52 12 49 14 35 29 I 08 17 10 27 09 28 11 37 31 II 02 45 05 05 05 12 07 28 31 I 02 47 04 56 03 57 06 06

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ECLIPSES, OCCULTATIONS AND TRANSITS

September cont'd Occultations and Eclipses Date Sat. OcD OcR EcD EcR

25 I 18 58 22 06 26 II 18 55 23 05 27 I 13 28 16 35 29 I 07 58 11 04 30 II 08 17 12 22 30 III 15 14 17 21 18 58 20 48

September cont'd Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

25 II 00 25 02 46 02 24 04 40 26 I 16 11 18 21 17 07 19 16 27 III 00 51 02 56 04 45 06 33 28 I 10 41 12 51 11 35 13 44 28 II 13 49 16 09 15 42 17 59 30 I 05 11 07 21 06 04 08 13

October Occultations and Eclipses Date Sat. OcD OcR EcD EcR

1 I 02 28 05 32 2/3 I 20 58 00 01 3/4 II 21 40 01 39 4 I 15 28 18 30 6 I 09 59 12 59 7 II 11 03 14 57 7/8 III 19 36 21 43 22 57 00 48 8 I 04 29 07 27 9/10 I 22 59 01 56 11 II 00 26 04 14 11 I 17 29 20 25 13 I 12 00 14 54 14 II 13 50 17 31 15 III 00 01 02 08 02 57 04 48 15 I 06 30 09 22 17 I 01 00 03 51 18 II 03 13 06 49 18 I 19 30 22 20 20 I 14 01 16 48 21 II 16 37 20 06 22 III 04 27 06 34 06 55 08 47 22 I 08 31 11 17 24 I 03 01 05 46 25 II 06 01 09 24 25/26 I 21 32 00 14 27 I 16 02 18 43 28 II 19 25 22 41 29 III 08 53 12 47 29 I 10 33 13 12 31 I 05 03 07 40

October Transits and Shadow Transits Date Sat. TrI TrE ShI ShE

1/ 2 I 23 41 01 51 00 32 02 42 2 II 03 13 05 34 05 01 07 18 3 I 18 11 20 21 19 01 21 10 4 III 05 12 07 17 08 44 10 33 5 I 12 41 14 51 13 30 15 39 5 II 16 37 18 58 18 19 20 36 7 I 07 11 09 21 07 58 10 08 9 I 01 41 03 51 02 27 04 36 9 II 06 02 08 23 07 38 09 55 10 I 20 11 22 21 20 55 23 05 11 III 09 34 11 40 12 42 14 32 12 I 14 41 16 51 15 24 17 34 12 II 19 26 21 47 20 56 23 13 14 I 09 11 11 21 09 53 12 02 16 I 03 41 05 52 04 21 06 31 16 II 08 51 11 12 10 14 12 32 17/18 I 22 11 00 22 22 50 01 00 18 III 13 58 16 04 16 40 18 30 19 I 16 41 18 52 17 18 19 28 19/20 II 22 16 00 37 23 32 01 50 21 I 11 12 13 22 11 47 13 57 23 I 05 42 07 52 06 16 08 25 23 II 11 41 14 02 12 51 15 09 25 I 00 12 02 23 00 44 02 54 25 III 18 24 20 30 20 39 22 30 26 I 18 42 20 53 19 13 21 23 27 II 01 06 03 27 02 09 04 27 28 I 13 12 15 23 13 41 15 51 30 I 07 43 09 53 08 10 10 20 30 II 14 31 16 53 15 27 17 45

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76 Satellites of Jupiter BAA Handbook 2018

ECLIPSES, OCCULTATIONS AND TRANSITS

December Occultations and Eclipses Date Sat. EcD EcR OcD OcR

23 I 07 46 10 24 24 II 17 02 20 22 25 I 02 14 04 55 25 III 18 39 22 43 26 I 20 43 23 25 28 II 06 19 09 47 28 I 15 11 17 55 30 I 09 40 12 25 31 II 19 37 23 11 32 I 04 08 06 55

December Transits and Shadow Transits Date Sat. ShI ShE TrI TrE

22 III 04 25 06 22 06 07 08 13 22 I 10 25 12 36 10 52 13 03 22/23 II 22 52 01 11 23 44 02 07 24 I 04 54 07 04 05 22 07 33 25/26 I 23 22 01 33 23 52 02 03 26 II 12 09 14 29 13 09 15 31 27 I 17 51 20 01 18 22 20 33 29 III 08 24 10 21 10 34 12 40 29 I 12 19 14 30 12 52 15 03 30 II 01 26 03 46 02 32 04 55 31 I 06 48 08 58 07 22 09 34

Jupiter in conjunction with the Sun: 2018 November 26d 7h

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BAA Handbook 2018 Saturn 77

SATURN Opposition: June 27 Conjunction: none

2018 Rings

RA Dec. Mag Equat Diam.

Polar Diam.

Major Axis

Minor Axis

DE Δ h m º ' " " " " º au

Jan. 2 18 6.5 –22 32 0.5 15.1 13.9 34.2 15.3 26.5 11.03112 18 11.5 –22 31 0.5 15.1 13.9 34.3 15.2 26.4 10.98922 18 16.4 –22 30 0.5 15.2 14.0 34.5 15.3 26.2 10.922

Feb. 1 18 20.9 –22 28 0.6 15.3 14.1 34.8 15.3 26.1 10.83211 18 25.2 –22 26 0.6 15.5 14.3 35.2 15.4 26.0 10.721

21 18 29.0 –22 23 0.6 15.7 14.5 35.6 15.5 25.8 10.591Mar. 3 18 32.3 –22 21 0.6 15.9 14.7 36.1 15.7 25.7 10.446

13 18 35.0 –22 19 0.5 16.2 14.9 36.7 15.8 25.6 10.28923 18 37.2 –22 17 0.5 16.4 15.1 37.2 16.0 25.5 10.126

Apr. 2 18 38.6 –22 15 0.5 16.7 15.4 37.9 16.3 25.5 9.959

12 18 39.4 –22 14 0.4 17.0 15.6 38.5 16.5 25.4 9.79422 18 39.5 –22 14 0.4 17.2 15.9 39.1 16.8 25.4 9.635

May 2 18 38.9 –22 15 0.3 17.5 16.1 39.8 17.1 25.4 9.48712 18 37.6 –22 16 0.3 17.8 16.4 40.3 17.4 25.5 9.35522 18 35.7 –22 18 0.2 18.0 16.6 40.8 17.6 25.6 9.242

Jun. 1 18 33.3 –22 20 0.2 18.2 16.7 41.2 17.8 25.7 9.15311 18 30.5 –22 23 0.1 18.3 16.8 41.5 18.0 25.8 9.09021 18 27.4 –22 25 0.1 18.4 16.9 41.7 18.2 25.9 9.055

Jul. 1 18 24.3 –22 28 0.0 18.4 16.9 41.7 18.3 26.0 9.05011 18 21.1 –22 31 0.1 18.3 16.9 41.6 18.3 26.1 9.075

21 18 18.2 –22 33 0.1 18.2 16.8 41.3 18.3 26.3 9.12831 18 15.7 –22 36 0.2 18.0 16.6 41.0 18.2 26.3 9.209

Aug. 10 18 13.6 –22 38 0.2 17.8 16.5 40.5 18.0 26.4 9.31320 18 12.1 –22 40 0.3 17.6 16.2 40.0 17.8 26.5 9.43930 18 11.2 –22 41 0.4 17.3 16.0 39.4 17.6 26.5 9.581

Sep. 9 18 11.0 –22 43 0.4 17.1 15.7 38.7 17.3 26.6 9.73519 18 11.6 –22 44 0.4 16.8 15.5 38.1 17.1 26.6 9.89829 18 12.8 –22 45 0.5 16.5 15.2 37.5 16.8 26.6 10.064

Oct. 9 18 14.7 –22 46 0.5 16.2 15.0 36.9 16.5 26.5 10.22819 18 17.3 –22 46 0.5 16.0 14.8 36.3 16.2 26.5 10.387

29 18 20.4 –22 46 0.5 15.8 14.5 35.8 15.9 26.4 10.535Nov. 8 18 24.0 –22 45 0.6 15.6 14.4 35.3 15.7 26.3 10.670

18 18 28.1 –22 44 0.6 15.4 14.2 35.0 15.4 26.2 10.78828 18 32.5 –22 42 0.5 15.3 14.1 34.6 15.2 26.0 10.887

Dec. 8 18 37.3 –22 39 0.5 15.2 14.0 34.4 15.0 25.9 10.962

18 18 42.2 –22 35 0.5 15.1 13.9 34.2 14.8 25.7 11.01428 18 47.3 –22 30 0.5 15.1 13.9 34.2 14.7 25.5 11.040

Description of the headings in the table can be found on page 20.

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78 Saturn BAA Handbook 2018

LONGITUDE OF CENTRAL MERIDIAN OF SATURNSYSTEM I

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 221.3 111.8 351.2 245.2 16.4 272.8 44.6 299.4 191.8 317.9 206.8 331.0 2 345.5 236.0 115.5 9.6 140.8 37.2 169.0 63.7 316.1 82.1 330.9 95.1 3 109.7 0.3 239.8 133.9 265.2 161.6 293.4 188.0 80.3 206.3 95.1 219.3 4 233.9 124.5 4.1 258.3 29.6 286.0 57.8 312.3 204.5 330.5 219.2 343.4 5 358.1 248.8 128.4 22.6 154.0 50.5 182.1 76.6 328.8 94.6 343.3 107.5 6 122.3 13.0 252.7 147.0 278.4 174.9 306.5 200.9 93.0 218.8 107.5 231.7 7 246.4 137.3 17.0 271.3 42.8 299.3 70.9 325.2 217.2 343.0 231.6 355.8 8 10.6 261.5 141.3 35.7 167.2 63.7 195.2 89.5 341.4 107.1 355.8 120.0 9 134.8 25.8 265.6 160.1 291.6 188.1 319.6 213.8 105.7 231.3 119.9 244.1 10 259.0 150.0 29.9 284.4 56.0 312.5 83.9 338.1 229.9 355.5 244.0 8.3 11 23.2 274.3 154.2 48.8 180.4 76.9 208.3 102.4 354.1 119.6 8.2 132.4 12 147.4 38.5 278.5 173.2 304.8 201.3 332.7 226.6 118.3 243.8 132.3 256.6 13 271.6 162.8 42.9 297.5 69.2 325.7 97.0 350.9 242.5 7.9 256.5 20.7 14 35.8 287.0 167.2 61.9 193.6 90.1 221.4 115.2 6.7 132.1 20.6 144.9 15 160.0 51.3 291.5 186.3 318.0 214.4 345.7 239.5 130.9 256.3 144.7 269.0 16 284.2 175.6 55.8 310.6 82.4 338.8 110.1 3.8 255.1 20.4 268.9 33.2 17 48.5 299.8 180.1 75.0 206.8 103.2 234.4 128.0 19.3 144.6 33.0 157.3 18 172.7 64.1 304.5 199.4 331.2 227.6 358.8 252.3 143.5 268.7 157.2 281.5 19 296.9 188.4 68.8 323.8 95.6 352.0 123.1 16.6 267.7 32.9 281.3 45.6 20 61.1 312.7 193.1 88.2 220.0 116.4 247.5 140.8 31.9 157.0 45.4 169.8 21 185.3 76.9 317.4 212.5 344.4 240.8 11.8 265.1 156.1 281.2 169.6 293.9 22 309.5 201.2 81.8 336.9 108.8 5.2 136.1 29.4 280.3 45.3 293.7 58.1 23 73.7 325.5 206.1 101.3 233.2 129.6 260.5 153.6 44.5 169.5 57.8 182.3 24 198.0 89.8 330.4 225.7 357.6 254.0 24.8 277.9 168.7 293.6 182.0 306.4 25 322.2 214.0 94.8 350.1 122.0 18.4 149.1 42.1 292.9 57.8 306.1 70.6 26 86.4 338.3 219.1 114.5 246.4 142.7 273.4 166.4 57.0 181.9 70.3 194.7 27 210.6 102.6 343.5 238.8 10.8 267.1 37.8 290.6 181.2 306.1 194.4 318.9 28 334.9 226.9 107.8 3.2 135.2 31.5 162.1 54.9 305.4 70.2 318.5 83.1 29 99.1 232.2 127.6 259.6 155.9 286.4 179.1 69.6 194.4 82.7 207.2 30 223.3 356.5 252.0 24.0 280.3 50.7 303.4 193.8 318.5 206.8 331.4 31 347.6 120.9 148.4 175.0 67.6 82.6 95.6

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 35.18 7 246.25 10 5.86 1 0.59 6 3.52 2 70.36 8 281.43 20 11.73 2 1.17 7 4.10 3 105.54 9 316.61 30 17.59 3 1.76 8 4.69 4 140.72 10 351.79 40 23.45 4 2.35 9 5.28 5 175.90 11 386.97 50 29.32 5 2.93 10 5.86 6 211.07 12 422.15 60 35.18

System I applies to all objects situated on or between the south component of the North Equatorial Belt and the north component of the South Equatorial Belt.

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BAA Handbook 2018 Saturn 79

LONGITUDE OF CENTRAL MERIDIAN OF SATURNSYSTEM II

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 145.4 114.5 169.4 142.1 24.2 359.2 242.0 215.5 186.7 63.9 31.5 266.8 2 237.2 206.4 261.4 234.1 116.3 91.3 334.1 307.5 278.7 155.8 123.4 358.6 3 329.1 298.4 353.4 326.1 208.3 183.4 66.2 39.5 10.6 247.7 215.2 90.5 4 61.0 30.3 85.4 58.2 300.4 275.5 158.2 131.5 102.5 339.5 307.1 182.3 5 152.9 122.3 177.4 150.3 32.5 7.6 250.3 223.5 194.5 71.4 38.9 274.2

6 244.8 214.2 269.4 242.3 124.6 99.7 342.4 315.5 286.4 163.3 130.8 6.0 7 336.7 306.1 1.4 334.4 216.7 191.8 74.4 47.5 18.3 255.2 222.6 97.9 8 68.6 38.1 93.4 66.4 308.8 283.9 166.5 139.5 110.2 347.0 314.4 189.7 9 160.5 130.0 185.4 158.5 40.9 16.0 258.6 231.5 202.2 78.9 46.3 281.6 10 252.4 222.0 277.4 250.5 133.0 108.1 350.6 323.5 294.1 170.8 138.1 13.4

11 344.3 313.9 9.4 342.6 225.1 200.2 82.7 55.5 26.0 262.6 230.0 105.3 12 76.2 45.9 101.5 74.7 317.2 292.3 174.7 147.5 117.9 354.5 321.8 197.1 13 168.1 137.9 193.5 166.7 49.3 24.4 266.8 239.5 209.8 86.4 53.7 289.0 14 260.0 229.8 285.5 258.8 141.4 116.5 358.9 331.4 301.7 178.2 145.5 20.8 15 351.9 321.8 17.5 350.9 233.5 208.6 90.9 63.4 33.6 270.1 237.3 112.7

16 83.8 53.7 109.5 82.9 325.6 300.7 183.0 155.4 125.5 1.9 329.2 204.5 17 175.7 145.7 201.5 175.0 57.7 32.8 275.0 247.4 217.5 93.8 61.0 296.4 18 267.6 237.7 293.6 267.1 149.8 124.9 7.1 339.4 309.4 185.6 152.9 28.2 19 359.5 329.6 25.6 359.2 241.9 217.0 99.1 71.3 41.3 277.5 244.7 120.1 20 91.4 61.6 117.6 91.2 334.0 309.1 191.1 163.3 133.2 9.4 336.5 211.9

21 183.3 153.6 209.6 183.3 66.1 41.2 283.2 255.3 225.1 101.2 68.4 303.8 22 275.2 245.6 301.7 275.4 158.2 133.3 15.2 347.2 316.9 193.1 160.2 35.6 23 7.2 337.5 33.7 7.5 250.3 225.4 107.3 79.2 48.8 284.9 252.1 127.5 24 99.1 69.5 125.7 99.6 342.4 317.4 199.3 171.1 140.7 16.8 343.9 219.4 25 191.0 161.5 217.8 191.6 74.5 49.5 291.3 263.1 232.6 108.6 75.7 311.2

26 282.9 253.5 309.8 283.7 166.6 141.6 23.3 355.0 324.5 200.5 167.6 43.1 27 14.9 345.5 41.8 15.8 258.7 233.7 115.4 87.0 56.4 292.3 259.4 134.9 28 106.8 77.5 133.9 107.9 350.8 325.8 207.4 178.9 148.3 24.2 351.3 226.8 29 198.7 225.9 200.0 82.9 57.9 299.4 270.9 240.2 116.0 83.1 318.7 30 290.6 318.0 292.1 175.0 149.9 31.4 2.8 332.0 207.9 174.9 50.5

31 22.6 50.0 267.1 123.5 94.8 299.7 142.4

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME h º h º m º m º m º 1 33.83 7 236.83 10 5.64 1 0.56 6 3.38 2 67.67 8 270.67 20 11.28 2 1.13 7 3.95 3 101.50 9 304.50 30 16.92 3 1.69 8 4.51 4 135.33 10 338.33 40 22.56 4 2.26 9 5.08 5 169.17 11 372.17 50 28.19 5 2.82 10 5.64 6 203.00 12 406.00 60 33.83

System II applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt. However System III is used more often for these regions.

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80 Saturn BAA Handbook 2018

LONGITUDE OF CENTRAL MERIDIAN OF SATURNSYSTEM III

Day Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. º º º º º º º º º º º º 1 69.4 1.1 22.3 317.5 163.4 101.1 307.7 243.8 177.6 18.7 308.9 148.0 2 160.0 91.8 113.1 48.3 254.3 192.0 38.6 334.6 268.4 109.3 39.5 238.6 3 250.7 182.6 203.9 139.2 345.2 282.9 129.4 65.4 359.1 200.0 130.2 329.2 4 341.4 273.3 294.6 230.0 76.1 13.8 220.3 156.2 89.8 290.7 220.8 59.9 5 72.1 4.0 25.4 320.9 167.0 104.7 311.2 247.0 180.5 21.3 311.4 150.5

6 162.8 94.8 116.2 51.7 257.8 195.6 42.0 337.8 271.3 112.0 42.1 241.1 7 253.5 185.5 207.0 142.6 348.7 286.5 132.9 68.6 2.0 202.7 132.7 331.8 8 344.1 276.3 297.8 233.4 79.6 17.4 223.7 159.4 92.7 293.3 223.3 62.4 9 74.8 7.0 28.6 324.3 170.5 108.3 314.6 250.1 183.4 24.0 314.0 153.1 10 165.5 97.8 119.4 55.1 261.4 199.2 45.5 340.9 274.1 114.6 44.6 243.7

11 256.2 188.5 210.2 146.0 352.3 290.0 136.3 71.7 4.8 205.3 135.3 334.4 12 346.9 279.2 301.0 236.9 83.2 20.9 227.2 162.5 95.6 296.0 225.9 65.0 13 77.6 10.0 31.8 327.7 174.1 111.8 318.0 253.3 186.3 26.6 316.5 155.6 14 168.3 100.8 122.6 58.6 265 202.7 48.9 344.1 277.0 117.3 47.2 246.3 15 259.0 191.5 213.4 149.4 355.9 293.6 139.7 74.8 7.7 207.9 137.8 336.9

16 349.7 282.3 304.3 240.3 86.8 24.5 230.6 165.6 98.4 298.6 228.4 67.6 17 80.4 13.0 35.1 331.2 177.7 115.4 321.4 256.4 189.1 29.2 319.1 158.2 18 171.1 103.8 125.9 62.0 268.6 206.3 52.2 347.1 279.8 119.9 49.7 248.9 19 261.8 194.5 216.7 152.9 359.4 297.2 143.1 77.9 10.5 210.5 140.3 339.5 20 352.5 285.3 307.5 243.8 90.3 28.0 233.9 168.7 101.2 301.2 231.0 70.2

21 83.2 16.1 38.3 334.6 181.2 118.9 324.7 259.4 191.8 31.8 321.6 160.8 22 173.9 106.8 129.2 65.5 272.1 209.8 55.6 350.2 282.5 122.5 52.2 251.5 23 264.6 197.6 220.0 156.4 3.0 300.7 146.4 80.9 13.2 213.1 142.9 342.1 24 355.3 288.4 310.8 247.3 93.9 31.6 237.2 171.7 103.9 303.8 233.5 72.8 25 86.1 19.2 41.6 338.1 184.8 122.4 328.1 262.4 194.6 34.4 324.1 163.4

26 176.8 109.9 132.5 69.0 275.7 213.3 58.9 353.2 285.3 125.0 54.8 254.1 27 267.5 200.7 223.3 159.9 6.6 304.2 149.7 83.9 15.9 215.7 145.4 344.8 28 358.2 291.5 314.1 250.8 97.5 35.1 240.5 174.7 106.6 306.3 236.0 75.4 29 88.9 45.0 341.7 188.4 126.0 331.3 265.4 197.3 37.0 326.7 166.1 30 179.7 135.8 72.5 279.3 216.8 62.1 356.2 288.0 127.6 57.3 256.7

31 270.4 226.7 10.2 153.0 86.9 218.3 347.4

CHANGE OF LONGITUDE IN INTERVALS OF MEAN TIME

h º h º m º m º m º 1 33.78 7 236.48 10 5.63 1 0.56 6 3.38 2 67.57 8 270.26 20 11.26 2 1.13 7 3.94 3 101.35 9 304.05 30 16.89 3 1.69 8 4.50 4 135.13 10 337.83 40 22.52 4 2.25 9 5.07 5 168.92 11 371.61 50 28.15 5 2.82 10 5.63 6 202.70 12 405.40 60 33.78

System III also applies to all objects situated north of the south component of the North Equatorial Belt or south of the north component of the South Equatorial Belt. This longitude system is based upon the rotation period of the planet’s magnetic field as defined by the International Astronomical Union.

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BAA Handbook 2018 Satellites of Saturn 81

SATELLITES OF SATURNMIMAS, ENCELADUS AND TETHYS

Mimas Enceladus Tethys Each fourth eastern elongation Each third eastern elongation Each second eastern elongation d h d h d h d h d h d h

Jan. 1 04.3 Jul. 4 21.54 22.8 8 16.08 17.3 12 10.4

12 11.8 16 04.916 06.3 19 23.320 00.8 23 17.823 19.3 27 12.227 13.8 31 06.731 08.3 Aug. 4 01.2

Feb. 4 02.8 7 19.67 21.3 11 14.1

11 15.8 15 08.515 10.3 19 03.019 04.8 22 21.522 23.3 26 16.026 17.8 30 10.4

Mar. 2 12.3 Sep. 3 04.96 06.8 6 23.4

10 01.3 10 17.913 19.8 14 12.317 14.2 18 06.821 08.7 22 01.325 03.2 25 19.828 21.7 29 14.3

Apr. 1 16.1 Oct. 3 08.85 10.6 7 03.39 05.1 10 21.8

12 23.6 14 16.316 18.0 18 10.820 12.5 22 05.324 06.9 25 23.828 01.4 29 18.3

May 1 19.9 Nov. 2 12.85 14.3 6 07.39 08.8 10 01.8

13 03.2 13 20.316 21.7 17 14.820 16.1 21 09.324 10.6 25 03.828 05.0 28 22.331 23.5 Dec. 2 16.9

Jun. 4 17.9 6 11.48 12.4 10 05.9

12 06.8 14 00.416 01.3 17 18.919 19.7 21 13.423 14.2 25 07.927 08.6 29 02.4

Jul. 1 03.1

Note: For intervening eastern elongations add: Mimas 0d 22.6h or 1d 21.2h or 2d 19.9h

Enceladus 1d 08.9h or 2d 17.8h

Tethys 1d 21.3h

Jan. 1 01.5 Jul. 5 01.25 04.2 9 03.89 06.9 13 06.4

13 09.6 17 09.117 12.3 21 11.721 15.0 25 14.325 17.7 29 17.029 20.4 Aug. 2 19.6

Feb. 2 23.1 6 22.27 01.8 11 00.9

11 04.5 15 03.515 07.2 19 06.219 09.9 23 08.823 12.5 27 11.527 15.2 31 14.2

Mar. 3 17.9 Sep. 4 16.87 20.6 8 19.5

11 23.2 12 22.116 01.9 17 0.820 04.6 21 03.524 07.2 25 06.228 09.9 29 08.8

Apr. 1 12.6 Oct. 3 11.55 15.2 7 14.29 17.9 11 16.9

13 20.5 15 19.617 23.2 19 22.322 01.8 24 01.026 04.5 28 03.730 07.1 Nov. 1 06.4

May 4 09.7 5 09.18 12.4 9 11.8

12 15.0 13 14.516 17.6 17 17.220 20.3 21 19.924 22.9 25 22.629 01.5 30 01.3

Jun. 2 04.2 Dec. 4 04.06 06.8 8 06.7

10 09.4 12 09.414 12.0 16 12.118 14.7 20 14.822 17.3 24 17.526 19.9 28 20.230 22.5

Jan. 2 0.1 Jul. 6 0.55 18.8 9 19.19 13.5 13 13.7

13 08.2 17 08.317 02.8 21 02.820 21.5 24 21.424 16.2 28 16.028 10.8 Aug. 1 10.6

Feb. 1 05.5 5 05.25 0.2 8 23.88 18.8 12 18.4

12 13.5 16 13.016 08.1 20 07.620 02.8 24 02.223 21.4 27 20.827 16.1 31 15.4

Mar. 3 10.7 Sep. 4 10.17 05.4 8 04.7

11 0.0 11 23.314 18.7 15 17.918 13.3 19 12.622 07.9 23 07.226 02.5 27 01.929 21.2 30 20.5

Apr. 2 15.8 Oct. 4 15.16 10.4 8 09.8

10 05.0 12 04.413 23.6 15 23.117 18.2 19 17.821 12.9 23 12.425 07.5 27 07.129 02.1 31 01.7

May 2 20.6 Nov. 3 20.46 15.2 7 15.1

10 09.8 11 09.714 04.4 15 04.417 23.0 18 23.121 17.6 22 17.825 12.2 26 12.429 06.8 30 07.1

Jun. 2 01.3 Dec. 4 01.85 19.9 7 20.59 14.5 11 15.1

13 09.1 15 09.817 03.6 19 04.520 22.2 22 23.224 16.8 26 17.828 11.4 30 12.5

Jul. 2 05.9

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82 Satellites of Saturn BAA Handbook 2018

SATELLITES OF SATURNDIONE AND RHEA

Dione Rhea Each second eastern elongation Each second eastern elongation d h d h d h d h d h d h

Jan. 1 01.4 Apr. 20 14.3 Aug. 8 00.4 Jan. 1 19.1 May 8 09.1 Sep. 11 18.8 6 12.9 26 01.6 13 11.8 10 20.3 17 09.8 20 19.7 12 00.4 May 1 12.9 18 23.1 19 21.5 26 10.5 29 20.7 17 11.9 7 00.3 24 10.5 28 22.7 Jun. 4 11.2 Oct. 8 21.7 22 23.4 12 11.6 29 21.8 Feb. 6 23.8 13 11.8 17 22.7 28 10.9 17 22.9 Sep. 4 09.2 16 00.9 22 12.4 26 23.8Feb. 2 22.4 23 10.2 9 20.6 25 02.0 Jul. 1 13.0 Nov. 5 00.9 8 09.9 28 21.5 15 08.0 Mar. 6 03.0 10 13.6 14 02.0 13 21.3 Jun. 3 08.8 20 19.4 15 04.0 19 14.3 23 03.2 19 08.8 8 20.1 26 06.8 24 05.0 28 14.9 Dec. 2 04.4 24 20.2 14 07.4 Oct. 1 18.2 Apr. 2 05.9 Aug. 6 15.6 11 05.5Mar. 2 07.7 19 18.7 7 05.7 11 06.8 15 16.4 20 06.7 7 19.1 25 06.0 12 17.1 20 07.6 24 17.1 29 07.9 13 06.5 30 17.3 18 04.6 29 08.4 Sep. 2 18.0 18 17.9 Jul. 6 04.6 23 16.0 24 05.4 11 15.9 29 03.5 29 16.8 17 03.2 Nov. 3 15.0 Note: For an intervening eastern elongation add:Apr. 4 04.1 22 14.5 9 02.4 9 15.5 28 01.8 14 13.9 Dione 2d 17.7h

15 02.9 Aug. 2 13.1 ---- -- ---- Rhea 4d 12.4h

TITAN AND HYPERION Titan Hyperion E. Elong. Inf. Conj’n W. Elong. Sup. Conj’n E.Elong. W Elong. d h d h d h d h d h d h

Jan. 6 02.1 Jan. 9 22.9 Jan. 14 03.4 18 06.7 Jan. 19 12.1 Jan. 30 02.6 22 02.9 25 23.7 30 04.2 Feb. 3 07.3 Feb. 10 00.0 Feb. 20 14.9Feb. 7 03.5 Feb. 11 00.3 Feb. 15 04.8 19 07.6 Mar. 3 10.9 Mar. 14 01.9 23 03.9 27 00.6 Mar. 3 05.0 Mar. 7 07.6 24 20.4 Apr. 4 11.2Mar. 11 03.8 Mar. 15 00.5 19 04.8 23 07.2 Apr. 15 04.4 25 18.6 27 03.4 30 23.9 Apr. 4 04.2 Apr. 8 06.4 May 6 10.8 May 17 00.2Apr. 12 02.4 Apr. 15 22.9 20 03.0 24 05.1 27 15.7 Jun. 7 04.2 28 01.0 May 1 21.4 May 6 01.3 May 10 03.3 Jun. 17 19.3 28 07.1May 13 23.1 17 19.4 21 23.2 26 01.2 Jul. 8 22.3 Jul. 19 09.5 29 20.8 Jun. 2 17.1 Jun. 6 20.6 Jun. 10 22.8 30 01.0 Aug. 9 12.2Jun. 14 18.2 18 14.5 22 17.9 26 20.2 Aug. 20 04.1 30 15.6 30 15.5 Jul. 4 11.8 Jul. 8 15.1 Jul. 12 17.6 Sep. 10 07.8 Sep. 20 20.1Jul. 16 12.8 20 09.2 24 12.4 28 15.2 Oct. 1 12.5 Oct. 12 01.8Aug. 1 10.4 Aug. 5 06.8 Aug. 9 10.1 Aug. 13 13.1 22 18.1 Nov. 2 08.6 17 08.3 21 04.8 25 08.2 29 11.3 Nov. 13 00.5 23 16.3Sep. 2 06.6 Sep. 6 03.3 Sep. 10 06.7 Sep. 14 10.1 Dec. 4 07.7 Dec. 15 00.8 18 05.4 22 02.3 26 05.8 30 09.3 25 15.4 Oct. 4 04.8 Oct. 8 01.8 Oct. 12 05.4 Oct. 16 08.9 20 04.5 24 01.7 28 05.5 Nov. 1 09.0 Nov. 5 04.7 Nov. 9 02.0 Nov. 13 05.9 17 09.3 21 05.2 25 02.5 29 06.6 Dec. 3 09.9 Dec. 7 05.9 Dec. 11 03.3 Dec. 15 07.5 19 10.7 23 06.8 27 04.3 31 08.5

Position-angle and angular-distances can be obtained from JPL’s Horizons web page at:http://ssd.jpl.nasa.gov/?horizons

(see page 114)

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BAA Handbook 2018 Satellites of Saturn 83

TITAN

Saturn is not in conjunction with Sun during 2018.

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84 Satellites of Saturn BAA Handbook 2018

IAPETUSIapetus shows variations in brightness, and is always brighter at western elongation than at eastern. The diagrams show the apparent path of Iapetus relative to Saturn, the units being in seconds of arc. Conjunction of Saturn is indicated by the faint portion of the orbit path from Jan.1 to Jan.20 and from Dec.2 to Dec.31. E. Elong. Inf. Conj’n. W. Elong. Sup. Conj’n. d h d h d h d h

Feb. 13 04.5 Mar. 4 09.7 Mar. 25 11.0 Apr. 14 20.4 May 4 04.1 May 22 20.6 Jun. 12 04.4 Jul. 2 09.2 Jul. 21 04.0 Aug. 9 02.5 Aug. 29 04.2 Sep. 19 03.0 Oct. 8 04.6 Oct. 27 18.7 Nov. 17 11.5 Dec. 8 19.0 Dec. 28 09.0

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BAA Handbook 2018 Uranus 85

URANUSUranus is at opposition on October 24, magnitude 5.7, diameter 3.7"

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86 Neptune BAA Handbook 2018

NEPTUNENeptune is at opposition on September 7, magnitude 7.8, diameter 2.4"

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BAA Handbook 2018 Trans-Neptunian Objects 87

Trans–Neptunian & Scattered–Disk Objects

The list comprises the date, magnitude, geocentric position and apparent motion when at opposition in 2018, of the 25 most intrinsically bright objects known as of 2017 March 27. The sizes of the smaller objects listed are often speculative given that they are based on an estimated albedo only. If you wish to observe an object then go to the website of the Minor Planet and Comet Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Here you enter the date and the designation of the object(s) you wish to observe. Given the extreme distance of these objects, the geocentric position will be sufficiently accurate for any location on the Earth.

Object Opposition Approx. MotionNumber/Name Prov ID Date V H Diam. Δ RA Dec. Speed P km au h m º ' "/min º

(136199) Eris 2003 UB313 Oct. 17 18.7 –1.1 2326 95.12 1 44.0 –2 13.1 0.025 252(134340) Pluto – Jul. 12 14.8 –0.4 2374 32.58 19 25.5 –21 48.8 0.061 258(136472) Makemake 2005 FY9 Mar. 24 17.0 –0.3 1450 51.64 13 02.0 +24 48.7 0.042 295(136108) Haumea 2003 EL61 Apr. 15 17.3 0.2 1500* 49.62 14 12.9 +17 04.6 0.043 293(90377) Sedna 2003 VB12 Nov. 19 20.8 1.5 1030 83.98 3 48.3 +7 38.6 0.026 257(225088) 2007 OR10 Aug. 27 21.2 1.8 1350 87.06 22 24.3 –12 12.3 0.026 251(90482) Orcus 2004 DW Feb. 28 19.1 2.2 940 47.13 10 12.3 –10 11.8 0.046 291(50000) Quaoar 2002 LM60 Jun. 22 18.7 2.4 890 41.88 18 03.3 –15 21.9 0.049 270 2013 FY27 Mar. 6 22.1 3.0 900 79.13 10 45.9 –6 51.9 0.029 295(174567) Varda 2003 MW12 Jun. 11 20.0 3.3 700 45.76 17 22.3 –1 44.9 0.045 275(55565) 2002 AW197 Feb. 19 20.0 3.4 730 44.52 9 49.0 –1 41.0 0.048 287(55636) 2002 TX300 Oct. 27 19.8 3.4 300 41.69 1 22.1 +35 31.0 0.051 247(202421) 2005 UQ513 Oct. 18 20.3 3.4 500 47.15 0 48.1 +33 11.7 0.045 245(229762) 2007 UK126 Dec. 4 19.8 3.5 610 41.24 4 50.8 +1 23.7 0.050 265 2014 UZ224 Nov. 5 23.1 3.5 635 89.75 3 13.0 –10 13.9 0.025 253(28978) Ixion 2001 KX76 Jun. 17 19.6 3.6 650 38.46 17 42.3 –28 48.7 0.054 268 2015 RR245 Oct. 2 21.7 3.7 670 61.99 0 25.5 +6 06.1 0.035 246 2010 RF43 Sep. 8 21.4 3.7 580 52.74 23 40.8 –25 25.2 0.041 248(208996) 2003 AZ84 Jan. 23 20.2 3.7 700 43.61 8 12.6 +8 46.3 0.050 281(20000) Varuna 2000 WR106 Jan. 20 20.1 3.7 700 42.90 8 16.8 +26 57.4 0.050 286(145452) 2005 RN43 Sep. 7 19.8 3.7 680 39.62 22 49.6 +1 05.0 0.052 244(303775) 2005 QU182 Oct. 12 20.9 3.7 420 51.85 1 28.0 –4 07.6 0.041 249(307261) 2002 MS4 Jul. 3 20.4 3.7 930 45.69 18 41.5 –6 37.1 0.046 267 2014 EZ51 May 20 21.2 3.7 660 54.68 15 41.9 –25 18.5 0.039 282(120178) 2003 OP32 Sep. 2 20.2 3.8 230 41.37 22 28.0 +2 57.4 0.051 244

*Haumea is asymmetric in shape being roughly 1940km x 1530km x 993km in size.

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88 Dwarf Planets BAA Handbook 2018

Pluto is at opposition, in Sagittarius, on July 12 at a mean visual magnitude of 14.2. Its brightness varies little during the year, ranging in mean visual magnitude from 14.2 to 14.5.Charts prepared using GUIDE 8.0. Stars down to magnitude 12.0 are shown.

DWARF PLANETS(134340) Pluto

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BAA Handbook 2018 Dwarf Planets 89

DWARF PLANETS(134340) Pluto

Detailed charts around the time of opposition. Jun. 12 to Jul. 12 Jul. 12 to Aug. 12

The charts show stars down to magnitude 14.

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90 Dwarf Planets BAA Handbook 2018

DWARF PLANETSORBITAL ELEMENTS

The geocentric data below have been extracted from the Minor Planet Center Ephemeris Service at: http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox J2000, Epoch of the elements, JD 2457400.5, 2016 Jan. 13.0 TT No. Name a e i Node Peri. M au ° ° ° ° 1 Ceres 2.768 0.076 10.592 80.310 72.908 266.802 134340 Pluto 39.652 0.253 17.138 110.295 113.954 39.277 136108 Haumea 43.353 0.189 28.201 121.920 239.096 213.102 136199 Eris 67.649 0.442 44.198 35.881 151.419 204.770 136472 Makemake 45.744 0.154 28.991 79.547 296.291 160.024

More information on asteroids and dwarf planets can be found on the website of the Asteroid and Remote Planets Section at: http://www.britastro.org/asteroids/

EPHEMERIDESThe data below have been extracted from the Minor Planet Center Ephemeris Service at:

http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

Equinox J2000, Epoch of the elements, JD 2457800.5, 2017 Feb. 16.0 TT

1 Ceres2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 9 32 59.3 +26 05 54 1.736 2.581 141.8 7.4 11 9 28 31.2 +27 26 35 1.666 2.577 152.2 7.2 21 9 21 26.3 +28 49 42 1.621 2.574 161.8 7.0 31 9 12 32.9 +30 06 05 1.602 2.571 166.7 6.9Feb. 10 9 03 00.8 +31 07 17 1.611 2.568 162.0 7.0 20 8 54 09.5 +31 47 37 1.647 2.566 152.6 7.2Mar. 2 8 47 12.6 +32 05 17 1.707 2.564 142.2 7.4 12 8 42 57.1 +32 02 00 1.787 2.562 132.1 7.6 22 8 41 44.7 +31 40 55 1.884 2.560 122.5 7.8Apr. 1 8 43 35.3 +31 05 29 1.992 2.559 113.5 7.9 11 8 48 11.9 +30 18 36 2.108 2.559 105.1 8.1 21 8 55 13.5 +29 22 15 2.229 2.558 97.3 8.3May 1 9 04 16.4 +28 17 49 2.353 2.558 89.9 8.4 11 9 14 57.2 +27 06 13 2.477 2.558 83.0 8.5 21 9 26 57.1 +25 48 01 2.599 2.559 76.5 8.6 31 9 39 58.9 +24 23 43 2.718 2.560 70.3 8.7Jun. 10 9 53 48.2 +22 53 47 2.833 2.561 64.3 8.7 20 10 08 14.8 +21 18 35 2.942 2.563 58.6 8.8 30 10 23 09.2 +19 38 40 3.045 2.565 53.0 8.8Jul. 10 10 38 24.4 +17 54 33 3.141 2.567 47.6 8.8 20 10 53 56.0 +16 06 46 3.229 2.570 42.3 8.8 30 11 09 39.4 +14 16 01 3.308 2.572 37.1 8.8Aug. 9 11 25 32.0 +12 22 54 3.379 2.576 32.0 8.8

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BAA Handbook 2018 Dwarf Planets 91

DWARF PLANETS134340 Pluto

2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Apr. 11 19 30 37.3 ‒21 29 33 33.528 33.540 89.8 15.1May 1 19 30 41.9 ‒21 31 07 33.206 33.553 109.3 15.0 21 19 29 58.3 ‒21 34 29 32.922 33.566 128.8 15.0Jun. 10 19 28 34.1 ‒21 39 19 32.710 33.579 148.3 14.9 30 19 26 42.1 ‒21 45 08 32.597 33.592 167.9 14.9 Jul. 20 19 24 38.9 ‒21 51 18 32.597 33.605 172.6 14.9Aug. 9 19 22 42.5 ‒21 57 09 32.711 33.618 153.0 14.9 29 19 21 10.4 ‒22 02 08 32.929 33.631 133.4 15.0Sep. 18 19 20 16.5 ‒22 05 49 33.226 33.644 113.8 15.0Oct. 8 19 20 10.2 ‒22 07 57 33.570 33.657 94.1 15.1

136108 Haumea2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 21 14 15 39.3 +16 16 07 50.431 50.518 94.5 17.4Feb. 10 14 15 44.5 +16 27 28 50.132 50.514 112.3 17.4Mar. 2 14 15 18.1 +16 40 10 49.878 50.510 129.2 17.3 22 14 14 24.8 +16 52 32 49.701 50.506 143.5 17.3Apr. 11 14 13 12.6 +17 02 53 49.621 50.502 151.2 17.3 May 1 14 11 52.0 +17 09 51 49.644 50.497 147.5 17.3 21 14 10 34.4 +17 12 33 49.767 50.493 135.5 17.3Jun. 10 14 09 30.2 +17 10 37 49.972 50.489 120.1 17.4 30 14 08 48.1 +17 04 19 50.235 50.485 103.6 17.4Jul. 20 14 08 33.7 +16 54 19 50.526 50.480 86.9 17.4

136199 Eris2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jun. 30 1 45 45.4 ‒1 56 06 96.386 96.119 74.5 18.8Jul. 20 1 45 55.6 ‒1 57 05 96.055 96.115 93.1 18.8Aug. 9 1 45 50.6 ‒1 59 31 95.730 96.111 111.8 18.8 29 1 45 30.9 ‒2 03 03 95.448 96.107 130.5 18.8Sep. 18 1 44 58.8 ‒2 07 11 95.241 96.103 149.0 18.8 Oct. 8 1 44 17.9 ‒2 11 21 95.134 96.099 165.0 18.8 28 1 43 33.2 ‒2 14 57 95.142 96.096 163.6 18.8Nov. 17 1 42 50.3 ‒2 17 24 95.264 96.092 146.6 18.8Dec. 7 1 42 14.9 ‒2 18 19 95.488 96.088 127.3 18.8 27 1 41 51.4 ‒2 17 28 95.784 96.084 107.4 18.8

136472 Makemake2018 RA Dec. ∆ r Elong. V h m s ° ' " au au ° Jan. 1 13 04 31.9 +24 02 03 52.412 52.506 95.0 17.1 21 13 04 37.9 +24 12 38 52.120 52.508 112.7 17.0Feb. 10 13 04 12.4 +24 24 56 51.876 52.510 129.6 17.0Mar. 2 13 03 19.4 +24 37 12 51.709 52.512 143.8 17.0 22 13 02 06.9 +24 47 42 51.639 52.514 151.1 17.0 Apr. 11 13 00 45.5 +24 54 55 51.675 52.516 146.7 17.0May 1 12 59 26.6 +24 57 52 51.810 52.518 134.2 17.0 21 12 58 21.0 +24 56 06 52.027 52.519 118.6 17.0Jun. 10 12 57 37.2 +24 49 49 52.299 52.521 102.1 17.1 30 12 57 21.0 +24 39 40 52.596 52.523 85.3 17.1

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92 Comets BAA Handbook 2018

The date of perihelion (T), perihelion distance (q), period (P) and the magnitude parameters H1 and K1 are given for each comet at perihelion in 2018, and also for those which are expected to be brighter than 14th magnitude during 2018. The brightest magnitude during 2018, with the approximate date and the elongation at this time are also given. Some periodic comets show a flat lightcurve with the comet at a similar brightness for over a month whilst others have a much more sharply defined maximum brightness.

The relation between perihelion (q), aphelion (Q) and semi–major axis (a) is: a = (Q + q)/2. If required, the mean daily motion (n, expressed in degrees) can be computed from: n = 0.985608/(a3/2). The period is given by Kepler’s third law: P2 = a3 (where P is expressed in sidereal years and a in Astronomical Units). Magnitude parameters are from determinations by the BAA’s Comet Section or from the Central Bureau for Astronomical Telegrams; the magnitude is usually given by V = H1 + 5 (log Δ) + K1 (log r), where Δ is the distance of the comet from Earth and r is its distance from the Sun, both in Astronomical Units. Note that some PC ephemeris programs require K1/2.5 to be entered rather than K1.

EPHEMERIDES

Orbital elements and/or ephemerides are available at : Minor Planet Center : http://www.minorplanetcenter.net/iau/MPEph/MPEph.html

BAA Comet Section webpage : http://www.britastro.org/comet

Comet Orbit Home webpage : http://jcometobs.web.fc2.com/

JPL Small-Body Database Browser : http://ssd.jpl.nasa.gov/sbdb.cgi#top

CHARTS

Reinder Bouma and Edwin van Dijk's astrosite Groningen has charts with suitable comparison stars for visual photometry of comets brighter than 10th – 11th magnitude :

http://www.shopplaza.nl/astro/comets/comets.htm

The BAA’s Computing Section website has charts for many comets, updated monthly:http://britastro.org/computing/charts_comet.html

and also the ability to see which comets are visible on any night using "What’s observable":

http://britastro.org/computing/applets_ecliptic.html

Further information about the visibility of the brighter objects will be included in the 2017 December BAA Journal.

The finder chart on page 93 shows the apparent path of comet 29P/Schwassmann-Wachmann during 2018. 29P is visible annually and since 2014 it has been especially active, exhibiting 10 or more outbursts each year.The charts on page 96 show the path across the sky of comets 21P/Giacobinni-Zinner and 46P/Wirtanen, which may reach naked eye brightness. 46P/Wirtanen is a special target for Pro-am observations in 2018.

COMETS

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BAA Handbook 2018 Comets 93

SCH

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SSM

AN

N-W

AC

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94 Comets BAA Handbook 2018

COMETSComet T q P H1 K1 Date of Elong. Maximum peak at peak Brightness au years yy mm dd ° 2017

PANSTARRS C/2015 ER61 May 9.94 1.04 6.9 8.4 2018 1 1 122 13.7Johnson C/2015 V2 Jun. 12.34 1.64 7.1 5.6 2018 1 1 41 12.7Vales P/2010 H2 Sep. 17.06 3.10 7.53 6.0 10.0 @ @ @ @ 12.9Schaumasse 24P/ Nov. 16.47 1.21 8.26 7.6 24.2 2018 1 1 61 11.7Tsuchinshan 62P/ Nov. 15.67 1.38 6.38 9.5 15.0 2018 1 1 84 12.5

2018 Petriew 185P/ Jan. 27.67 0.93 5.46 10.7 19.6 2018 1 29 44 10.8LINEAR 197P/ Jan. 28.84 1.06 4.85 16.5 5.0 2018 1 27 28 17.9McNaught-Hughes 130P/ Jan. 21.76 1.82 6.22 12.5 10.0 2018 1 5 15 17.3Jacques C/2017 K6 Jan. 3.08 2.00 11.0 10.0 2018 1 1 85 15.3ATLAS C/2017 K4 Jan. 15.64 2.55 10.0 10.0 2018 1 1 23 16.8Smirnova-Chernykh 74P/ Jan. 26.71 3.54 8.48 5.0 15.0 2018 3 10 171 15.3McNaught 350P/ Jan. 29.25 3.75 8.38 14.0 10.0 2018 5 5 177 22.0Kowalski C/2016 Q4 Jan. 26.61 7.09 7.0 10.0 2018 10 12 168 19.5WISE 245P/ Feb. 8.04 2.16 8.06 14.0 10.0 2018 7 22 134 19.2Larson 250P/ Feb. 1.53 2.21 7.21 14.5 10.0 2018 1 13 165 18.4PANSTARRS C/2015 O1 Feb. 19.03 3.73 6.2 7.6 2018 4 1 114 13.1LINEAR 235P/ Mar. 17.46 2.73 7.97 12.0 10.0 2018 3 20 174 17.6PANSTARRS C/2017 K1 Mar. 26.14 7.26 7.0 10.0 2018 4 27 176 19.6NEAT 169P/ Apr. 29.60 0.60 4.20 16.0 5.0 2018 4 27 3 15.9PANSTARRS 282P/ Apr. 11.68 2.40 5.59 15.0 10.0 2018 12 7 157 20.6Lemmon C/2015 XY1 Apr. 29.92 7.93 5.5 10.0 2018 1 1 170 18.7Wilson-Harrington 107P/ May 23.53 0.97 4.26 15.0 5.0 2018 5 15 30 16.1du Toit 66P/ May 19.14 1.29 14.90 12.0 9.5 2018 5 17 84 12.8Forbes 37P/ May 4.10 1.61 6.43 9.5 10.0 2018 7 6 110 12.1PANSTARRS 253P/ May 7.75 2.04 6.46 14.5 10.0 2018 11 17 133 19.6NEAT 240P/ May 16.22 2.13 7.62 12.0 10.0 2018 1 1 76 17.6Kowal-Mrkos 143P/ May 7.30 2.53 8.91 14.0 5.0 2018 4 11 173 17.0PANSTARRS C/2016 R2 May 9.60 2.60 2.5 10.0 2018 1 11 133 8.7LONEOS 159P/ May 22.80 3.63 14.19 10.0 10.0 2018 12 9 155 18.1LINEAR 187P/ May 26.64 3.88 9.86 9.0 10.0 2018 5 25 167 17.2PANSTARRS P/2013 CU129 Jun. 24.34 0.80 4.88 15.2 10.0 2018 7 8 38 11.4Swift-Gehrels 64P/ Jun. 14.35 1.38 9.34 9.0 20.0 2018 6 14 27 13.5Christensen 64P/ Jun. 31.41 1.69 7.01 11.0 10.0 2018 7 18 32 15.2Catalina P/2011 CR42 Jun. 22.57 2.52 6.58 13.0 5.0 2018 5 1 172 16.0Gehrels 82P/ Jun. 28.61 3.63 8.43 7.5 15.0 2018 1 1 151 18.2LONEOS 267P/ Jul. 22.32 1.24 5.76 19.5 10.0 2018 7 24 82 20.2Arend-Rigaux 49P/ Jul. 15.50 1.43 6.74 9.6 10.0 2018 7 16 12 13.1PANSTARRS C/2016 N6 Jul. 18.21 2.67 7.0 10.0 2018 4 3 91 13.7Spacewatch 125P/ Aug. 27.95 1.52 5.52 15.5 10.0 2018 8 3 59 18.6Johnson 48P/ Aug. 12.20 2.00 6.54 7.0 12.3 2018 8 19 163 10.8Singer Brewster 105P/ Aug. 10.32 2.04 6.46 12.5 15.0 2018 5 5 139 18.1PANSTARRS C/2016 M1 Aug. 10.19 2.21 5.0 10.0 2018 6 28 156 9.1NEAT 243P/ Aug. 26.04 2.45 7.50 12.5 10.0 2018 10 12 165 17.3

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BAA Handbook 2018 Comets 95

COMETS

Giacobini-Zinner 21P/ Sep. 10.34 1.01 6.54 5.4 30.8 2018 9 8 79 3.6du Toit-Hartley 79P/ Sep. 13.34 1.12 5.05 14.0 15.0 2018 9 12 17 16.3Kearns-Kwee 59P/ Sep. 16.76 2.36 9.53 7.5 20.0 2018 12 17 140 16.4Elst-Pizarro 133P/ Sep. 20.75 2.66 5.62 12.0 10.0 2018 6 26 173 17.4Grigg-Skjellerup 26P/ Oct. 1.82 1.08 5.23 12.0 40.0 2018 9 30 13 14.9Catalina 300P/ Nov. 2.08 0.83 4.44 17.5 10.0 2018 11 9 47 17.0Stephan-Oterma 38P/ Nov. 10.97 1.59 37.95 3.5 30.0 2018 11 21 123 9.2Wirtanen 46P/ Dec. 12.96 1.06 5.44 8.2 15.9 2018 12 13 164 2.9LINEAR 247P/ Dec. 2.10 1.49 7.91 17.5 5.0 2018 12 31 122 17.8Tsuchinshan 60P/ Dec. 11.23 1.62 6.58 10.5 15.0 2018 12 31 109 13.8Shoemaker-Levy 137P/ Dec. 13.39 1.93 9.61 14.5 10.0 2018 9 24 138 18.0ODAS 198P/ Dec. 13.89 2.01 6.84 10.5 15.0 2018 11 25 173 15.1Catalina-PANSTARRS Dec. 6.44 2.20 5.28 14.0 10.0 2018 8 19 163 18.2(P/2013 R3)

2019Spahr 171P/ Jan. 13.71 1.77 6.71 10.2 15.0 2018 12 21 150 13.6ATLAS C/2017 M4 Jan. 1.39 2.98 6.0 10.0 2018 8 11 97 13.6Taylor 69P/ Mar. 18.28 2.28 7.68 7.3 10.0 2018 12 5 142 12.0Schwassmann-Wachmann Mar. 7.76 5.77 14.79 0.5 10.0 @ @ @ @ 11.529P/Gehrels 78P/ Apr. 2.70 2.01 7.23 -2.7 40.7 2018 12 31 63 12.7

@ Subject to outburst

Note : Vales P/2010 H2 - this comet has not been seen since 2010 when it became visible following its outburst at that time.

Comet (cont'd) T q P H1 K1 Date of Elong. Maximum peak at peak Brightness au years yy mm dd °

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96 Comets BAA Handbook 2018

COMETS

46P/

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BAA Handbook 2018 Meteor Diary 97

METEORSThis diary includes all regular major and some of the more reliable minor streams. Radiant data (UT, Alt.) and twilight data are for observers at the standard latitudes 52°N and 35°S, on the Greenwich meridian. Moonrise and moonset may be determined from the data on pages 27-31. Where two radiants are given for one shower, the first of the two listed in the table has been used for calculating the altitudes. All times are in UT. Normal limits are the dates between which the shower rates are normally greater than 25 per cent of the sporadic rate for the period.

Zenithal Hourly Rate (ZHR) is the probable hourly rate for a single experienced observer watching a clear sky with limiting magnitude 6.5 with the shower radiant at the zenith. To a first approximation, the observed hourly rate (OHR) is given by:

OHR = ZHR sin α

where α is the radiant elevation. Hence high rates cannot be expected if the radiant is low. Sky conditions can alter rates considerably and consequently observers should record the approximate naked eye limiting magnitude in the areas being watched during each observing session. The rates given are the maximum ones, and are only a guide in view of the inherent variability of showers.

Twilight here is nautical, starting and ending when the Sun is 12° below the horizon.

Telescopic Activity: If a number is given this is an approximate relative telescopic rate (sporadic rate = 1.0). If there is no entry the shower is deficient in faint meteors. However, many of the numbers are speculative. Observations using wide-field CCD imaging may help augment telescopic meteor work in the future.

Radiant Daily Motion: Where available, these come from the Working List of Meteor Showers published by the IAU Meteor Data Center (MDC). Meteor radiants are not stationary because of the Earth’s motion around the Sun. They move about one degree of ecliptic longitude per day. The daily motions should be applied to determine the radiant positions at dates other than maximum. The positions of several shower radiants at maximum have been revised following analysis of recent video meteor data by Alex Pratt, William Stewart and Leonard Entwisle.

Special Notes for 2018: Bright moonlight has an adverse effect on meteor observing, and for about five days to either side of Full Moon, lunar glare swamps all but the brighter meteors. Visual observers may, however, minimize the effects of moonlight by positioning themselves so the Moon is behind them and hidden behind a wall or other suitable obstruction. Fortunately, in 2018, relatively few of the major showers are seriously affected by moonlight. The Quadrantids in early January will be affected by a waning gibbous Moon in Cancer, observations of the Eta Aquarids in early May will be hampered by a waning gibbous Moon in Sagittarius, the Orionids in mid-to-late October will be affected after maximum by bright moonlight, and observations of the Ursids in late December will be seriously hindered by a full Moon.

There are many excellent observing opportunities in 2018. The April Lyrids are best observed after midnight, by which time the first quarter Moon will have set. The complex of showers which peak in late July, e.g. the Capricornids, early Delta Aquarids and Piscis Australids are not well placed with respect to the Moon this year, but those reaching maximum in early August, e.g. late Delta Aquarids, Alpha Capricornids and Iota Aquarids will be observable in darker skies. The Perseids are ideally placed this year with the main period of activity before and after the peak observable in moonless skies. Apart from the late Orionids, conditions for the major autumn showers are also very favourable in 2018. The Taurids in late October/early November, the Leonids in mid-November and the Geminids in mid-December are all observable without moonlight interfering. This year's "wild card" entry, the Draconids on October 8/9, coincide with New Moon but rates are expected to be low - only 10-20 meteors per hour - because the Earth passes too far from most of the dust trails laid down by the parent comet. However, unexpected outbursts in activity are always possible and observations of this shower will be very important in 2018.

It is hoped that observers will make a particular effort to take advantage of the favourable observing conditions throughout 2018. As always, observations away from the major shower maxima and of year-round sporadic activity are every bit as important to the work of the Association’s Meteor Section as those obtained when high rates are anticipated.

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98 Meteor Diary BAA Handbook 2018

METEORS METEORS

EpochRadiant Position Latitude 52°N Latitude 35°S

Notes

Maximum Daily Motion Twilight Radiant Twilight Radiant

Showerλ☉

(2000.0) Maximum Normal Limits ZHR

at Max.R.A. Dec. R.A. Dec. Telescopic

ActivityLocal Time of Transit Date

Age of Moon Ends Begins UT Alt. Ends Begins UT Alt.

° hh:mm (°) ° ° ° h d h h h ° h h h °Quadrantids 283.2 Jan. 3d 21h Jan. 1-6 80+ 15 20 (230) +50 +0.4 -0.2 1.5 8.5 Jan. 3 17 17.4 6.7 00

0306

214066

– – – – Blue and yellow meteors. Diffuse radiant except at peak. High rates in 2014. Unfavourable.

Virginids 022 Apr. 11-12 Mar-Apr Apr. 6-17

55

14:04 (211)13:36 (204)

–09–11

? ?

0.7 0.3

Apr. 11 25 20.2 3.9 220104

202916

18.6 5.4 200004

216238

The two most prominent of several radiants in Virgo, active March-April. Slow, long paths.

Lyrids 032 Apr. 22 Apr. 18-25 10 18:08 (272) +33 +1.1 0.0 –

4.2 Apr. 22 7 20.6 3.4 210003

154166

18.4 5.6 010305

092122

Normally rather moderate activity, but fine displays in 1803, 1922, 1982. Very favourable.

η Aquarids 45 May 5-6 Apr. 24-May 20

40 22:30 (338) –01 +0.7 +0.3 – 7.6 May 5 20 21.1 2.8 0203

0312

18.2 5.7 020406

052949

Fine southern shower, poorly seen from the UK. Broad maximum and multiple radiant. Telescopic peak λ☉=042°.

α-Scorpiids 038052

Apr. 28May 12

Apr. 20-May 19

5 16:31 (248)16:04 (241)

–24–24

+0.5 –0.19 1.5 2.01.6

Apr. 28May 12

13 27

20.821.3

3.1 2.5

22 0002

07 1412

18.1 5.8 200003

307757

Part of the Scorpio-Sagittarius complex. Several weak radiants. April-July.

Ophiuchids 079089

Jun. 10Jun. 20

May 19-July 5 17:56 (269)17:20 (260)

–23–20

– 23.5

Jun. 10Jun. 20

268

22.422.5

1.61.5

220002

151810

17.9 6.1 210003

547442

Weak activity from several radiants. Best for southern observers.

α-Cygnids 118148

Jul. 21Aug. 21

Jul.-Aug. 5 21:00 (315) +48 ? 1.123.0

Jul. 21Aug. 21

810

21.920.6

2.33.5

220002

628079

18.1 6.1 230102

030706

Weak, apparently stationary radiant producing steady activity throughout northern summer.

Capricornids 106113123

Jul. 9Jul. 16Jul. 26

Jul.-Aug. 5 20:44 (311) –15 –

1.6 1.20.5

Jul. 9Jul. 16Jul. 26

25313

22.322.121.7

1.92.12.5

220002

112122

18.1 6.1 210003

546406

Bright yellow-blue meteors. May have three maxima and multiple radiant. Favourable in the first half of July.

δ-Aquarids 126134

Jul. 29Aug. 6

Jul.15-Aug.20

2010

22 36 (339)23 04 (346)

-17+02

+0.8+1.0

+0.18+0.2

1.0 2.22.1

Jul. 29Aug. 6

1624

21.621.2

2.62.9

230103

091920

18.2 6.0 230205

447249

Fine southern shower with double radiant. S. component is the richer. Meteors tend to be faint.

Piscis Australids

128 Jul. 31 Jul. 15- Aug. 20

5 22 40 (340) -30 ? 2.1 Jul. 31 18 21.5 2.7 000102

030708

18.3 6.0 230205

518553

Southern shower in need of observation. Unfavourable.

α-Capricornids 130 Aug. 2-3 Jul. 15-Aug. 20

5 20:36 (309) –10 +0.9 +0.3 - 23.8 Aug. 2 20 21.4 2.8 220002

232822

18.3 5.9 230205

436541

Maxima at λ☉ =123°, 129°, 137°. Long, slow fireballs are often seen.

ι-Aquarids 134 Aug. 6 Jul.-Aug. 8 22:10 (333)22:04 (331)

–15–06

+1.07+1.03

+0.18+0.13

1.0? 1.21.1

Aug. 6 24 21.2 2.9 220002

122122

18.3 5.9 220104

386852

Rich in faint meteors. Double radiant.Favourable.

Perseids 140.0 Aug 13d 01h Jul. 23- Aug. 20

80+ 03 11 (048) +58 +1.38 +0.18 0.5 5.8 Aug. 13 2 21.0 3.2 210003

274466

– – – – Rich shower of fast meteors. High proportion of bright events leaving persistent trains. Very favourable.

Piscids 166178200

Sep. 9Sep. 21Oct. 13

Sep.-Oct. 105?

00:36 (009)00:24 (006)01:44 (026)

+0700

+14

? 1.30.30.1

Sep. 9Sep. 21Oct. 13

29 19.719.218.4

4.14.55.1

210003

21 4241

18.7 5.2 21 16 Another multiple-radiant ecliptic complex with low rates.

Draconids 195.35 - 195.4

Oct. 8d 23h-00h

Oct 7-10 20? 17 31 (263) +56 16.6 Oct. 8 29 18.6 5.0 192123

685238

– – – – Periodic shower connected with 21P/Giacobini-Zinner. Only weak activity expected. Very favourable.

Orionids 209 Oct. 21-24 Oct. 16-30 25 06 24 (096) +16 +0.70 +0.11 1.0 4.5 Oct. 22 13 18.1 5.4 000204

264353

19.3 4.2 000204

092940

Fast meteors, many with persistent trains. Flat maximum, with several sub-peaks. Good in 2007. Unfavourable.

Taurids (S) 223 (N) 230

Nov. 5-Nov. 12

Oct. 20- Nov. 30

10 03:33 (056)03:54 (059)

+13+22

+0.73+0.80

+0.18+0.16

? 0.60.5

Nov. 5Nov. 12

275

17.717.5

5.85.9

210003

335142

19.5 3.9 210003

193630

Slow meteors. Double radiant. Broad peak λ☉ =220°-230°. Sometimes more fireballs, as in 2015. Favourable.

Leonids 235.4 Nov. 18d 01h Nov. 15-20 20? 10 16 (154) +22 +0.6 -0.29 0.5? 6.5 Nov. 17 10 17.4 6.1 010305

234156

19.8 3.7 020304

051524

Very fast meteors, many with persistent trains. Enhanced activity unlikely until the late 2020s, but observations still important. Favourable.

Puppids-Velids 257274

Dec. 9-Dec. 26

Nov. 27-Jan 15 09 00 (135)09 20 (140)

–48–65

? 6.4 Dec. 9Dec.26

219

– – – – 20.2 3.5 230103

133150

Two of several radiants in Puppis, Vela and Carina from November to January

Geminids 262.0 Dec. 14d 08h Dec. 8-17 100+ 07 33 (113) +32 +1.02 -0.15 1.5 1.9 Dec. 14 7 17.2 6.6 210003

346167

20.2 3.6 230103

122231

Richest of the annual showers, with slow meteors and a good proportion of bright events. Favourable.

Ursids 271 Dec. 22-23 Dec. 17-25 10? 14 28 (217) +78 +0.88 -0.45 1.0? 8.4 Dec. 22 15 17.3 6.7 220206

414961

– – – – Under-observed shower which has produced outbursts in 1945, 1982, 1986 and in 2014. Unfavourable.

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BAA Handbook 2018 Meteor Diary 99

METEORS METEORS

EpochRadiant Position Latitude 52°N Latitude 35°S

Notes

Maximum Daily Motion Twilight Radiant Twilight Radiant

Showerλ☉

(2000.0) Maximum Normal Limits ZHR

at Max.R.A. Dec. R.A. Dec. Telescopic

ActivityLocal Time of Transit Date

Age of Moon Ends Begins UT Alt. Ends Begins UT Alt.

° hh:mm (°) ° ° ° h d h h h ° h h h °Quadrantids 283.2 Jan. 3d 21h Jan. 1-6 80+ 15 20 (230) +50 +0.4 -0.2 1.5 8.5 Jan. 3 17 17.4 6.7 00

0306

214066

– – – – Blue and yellow meteors. Diffuse radiant except at peak. High rates in 2014. Unfavourable.

Virginids 022 Apr. 11-12 Mar-Apr Apr. 6-17

55

14:04 (211)13:36 (204)

–09–11

? ?

0.7 0.3

Apr. 11 25 20.2 3.9 220104

202916

18.6 5.4 200004

216238

The two most prominent of several radiants in Virgo, active March-April. Slow, long paths.

Lyrids 032 Apr. 22 Apr. 18-25 10 18:08 (272) +33 +1.1 0.0 –

4.2 Apr. 22 7 20.6 3.4 210003

154166

18.4 5.6 010305

092122

Normally rather moderate activity, but fine displays in 1803, 1922, 1982. Very favourable.

η Aquarids 45 May 5-6 Apr. 24-May 20

40 22:30 (338) –01 +0.7 +0.3 – 7.6 May 5 20 21.1 2.8 0203

0312

18.2 5.7 020406

052949

Fine southern shower, poorly seen from the UK. Broad maximum and multiple radiant. Telescopic peak λ☉=042°.

α-Scorpiids 038052

Apr. 28May 12

Apr. 20-May 19

5 16:31 (248)16:04 (241)

–24–24

+0.5 –0.19 1.5 2.01.6

Apr. 28May 12

13 27

20.821.3

3.1 2.5

22 0002

07 1412

18.1 5.8 200003

307757

Part of the Scorpio-Sagittarius complex. Several weak radiants. April-July.

Ophiuchids 079089

Jun. 10Jun. 20

May 19-July 5 17:56 (269)17:20 (260)

–23–20

– 23.5

Jun. 10Jun. 20

268

22.422.5

1.61.5

220002

151810

17.9 6.1 210003

547442

Weak activity from several radiants. Best for southern observers.

α-Cygnids 118148

Jul. 21Aug. 21

Jul.-Aug. 5 21:00 (315) +48 ? 1.123.0

Jul. 21Aug. 21

810

21.920.6

2.33.5

220002

628079

18.1 6.1 230102

030706

Weak, apparently stationary radiant producing steady activity throughout northern summer.

Capricornids 106113123

Jul. 9Jul. 16Jul. 26

Jul.-Aug. 5 20:44 (311) –15 –

1.6 1.20.5

Jul. 9Jul. 16Jul. 26

25313

22.322.121.7

1.92.12.5

220002

112122

18.1 6.1 210003

546406

Bright yellow-blue meteors. May have three maxima and multiple radiant. Favourable in the first half of July.

δ-Aquarids 126134

Jul. 29Aug. 6

Jul.15-Aug.20

2010

22 36 (339)23 04 (346)

-17+02

+0.8+1.0

+0.18+0.2

1.0 2.22.1

Jul. 29Aug. 6

1624

21.621.2

2.62.9

230103

091920

18.2 6.0 230205

447249

Fine southern shower with double radiant. S. component is the richer. Meteors tend to be faint.

Piscis Australids

128 Jul. 31 Jul. 15- Aug. 20

5 22 40 (340) -30 ? 2.1 Jul. 31 18 21.5 2.7 000102

030708

18.3 6.0 230205

518553

Southern shower in need of observation. Unfavourable.

α-Capricornids 130 Aug. 2-3 Jul. 15-Aug. 20

5 20:36 (309) –10 +0.9 +0.3 - 23.8 Aug. 2 20 21.4 2.8 220002

232822

18.3 5.9 230205

436541

Maxima at λ☉ =123°, 129°, 137°. Long, slow fireballs are often seen.

ι-Aquarids 134 Aug. 6 Jul.-Aug. 8 22:10 (333)22:04 (331)

–15–06

+1.07+1.03

+0.18+0.13

1.0? 1.21.1

Aug. 6 24 21.2 2.9 220002

122122

18.3 5.9 220104

386852

Rich in faint meteors. Double radiant.Favourable.

Perseids 140.0 Aug 13d 01h Jul. 23- Aug. 20

80+ 03 11 (048) +58 +1.38 +0.18 0.5 5.8 Aug. 13 2 21.0 3.2 210003

274466

– – – – Rich shower of fast meteors. High proportion of bright events leaving persistent trains. Very favourable.

Piscids 166178200

Sep. 9Sep. 21Oct. 13

Sep.-Oct. 105?

00:36 (009)00:24 (006)01:44 (026)

+0700

+14

? 1.30.30.1

Sep. 9Sep. 21Oct. 13

29 19.719.218.4

4.14.55.1

210003

21 4241

18.7 5.2 21 16 Another multiple-radiant ecliptic complex with low rates.

Draconids 195.35 - 195.4

Oct. 8d 23h-00h

Oct 7-10 20? 17 31 (263) +56 16.6 Oct. 8 29 18.6 5.0 192123

685238

– – – – Periodic shower connected with 21P/Giacobini-Zinner. Only weak activity expected. Very favourable.

Orionids 209 Oct. 21-24 Oct. 16-30 25 06 24 (096) +16 +0.70 +0.11 1.0 4.5 Oct. 22 13 18.1 5.4 000204

264353

19.3 4.2 000204

092940

Fast meteors, many with persistent trains. Flat maximum, with several sub-peaks. Good in 2007. Unfavourable.

Taurids (S) 223 (N) 230

Nov. 5-Nov. 12

Oct. 20- Nov. 30

10 03:33 (056)03:54 (059)

+13+22

+0.73+0.80

+0.18+0.16

? 0.60.5

Nov. 5Nov. 12

275

17.717.5

5.85.9

210003

335142

19.5 3.9 210003

193630

Slow meteors. Double radiant. Broad peak λ☉ =220°-230°. Sometimes more fireballs, as in 2015. Favourable.

Leonids 235.4 Nov. 18d 01h Nov. 15-20 20? 10 16 (154) +22 +0.6 -0.29 0.5? 6.5 Nov. 17 10 17.4 6.1 010305

234156

19.8 3.7 020304

051524

Very fast meteors, many with persistent trains. Enhanced activity unlikely until the late 2020s, but observations still important. Favourable.

Puppids-Velids 257274

Dec. 9-Dec. 26

Nov. 27-Jan 15 09 00 (135)09 20 (140)

–48–65

? 6.4 Dec. 9Dec.26

219

– – – – 20.2 3.5 230103

133150

Two of several radiants in Puppis, Vela and Carina from November to January

Geminids 262.0 Dec. 14d 08h Dec. 8-17 100+ 07 33 (113) +32 +1.02 -0.15 1.5 1.9 Dec. 14 7 17.2 6.6 210003

346167

20.2 3.6 230103

122231

Richest of the annual showers, with slow meteors and a good proportion of bright events. Favourable.

Ursids 271 Dec. 22-23 Dec. 17-25 10? 14 28 (217) +78 +0.88 -0.45 1.0? 8.4 Dec. 22 15 17.3 6.7 220206

414961

– – – – Under-observed shower which has produced outbursts in 1945, 1982, 1986 and in 2014. Unfavourable.

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100 Variable Stars BAA Handbook 2018

VARIABLE STARSHeliocentric Times of Primary Minima

RZ Cassiopeiae: Magnitude 6.2 to 7.7, Duration 4.8 hours h h h h h hJan 2 3.9* Feb 1 1.0* Mar 1 17.5 Apr 1 19.3 May 1 16.5 Jun 1 18.3 3 8.6 2 5.7 2 22.2* 3 0.0* 2 21.2 2 23.0 4 13.3 3 10.4 4 2.9* 4 4.7 4 1.9* 4 3.7 5 17.9 4 15.1 5 7.6 5 9.4 5 6.6 5 8.4 6 22.6* 5 19.8* 6 12.3 6 14.1 6 11.3 6 13.1 8 3.3* 7 0.5* 7 16.9 7 18.8 7 15.9 7 17.8 9 8.0 8 5.2 8 21.6* 8 23.5* 8 20.6 8 22.5 10 12.7 9 9.8 10 2.3* 10 4.2 10 1.3* 10 3.2 11 17.4 10 14.5 11 7.0 11 8.8 11 6.0 11 7.8 12 22.1* 11 19.2 12 11.7 12 13.5 12 10.7 12 12.5 14 2.7* 12 23.9* 13 16.4 13 18.2 13 15.4 13 17.2 15 7.4 14 4.6* 14 21.1* 14 22.9* 14 20.1 14 21.9 16 12.1 15 9.3 16 1.7* 16 3.6 16 0.7* 16 2.5 17 16.8 16 14.0 17 6.4 17 8.3 17 5.4 17 7.3 18 21.5* 17 18.6 18 11.1 18 13.0 18 10.1 18 12.0 20 2.2* 18 23.3* 19 15.8 19 17.6 19 14.8 19 16.7 21 6.9 20 4.0* 20 20.5 20 22.3* 20 19.5 20 21.3 22 11.5 21 8.7 22 1.2* 22 3.0* 22 0.2* 22 2.0 23 16.2 22 13.4 23 5.9 23 7.7 23 4.9 23 6.7 24 20.9* 23 18.1 24 10.5 24 12.4 24 9.6 24 11.4 26 1.7* 24 22.8* 25 15.2 25 17.1 25 14.2 25 16.1 27 6.3 26 3.4* 26 19.9 26 21.8 26 18.9 26 20.8 28 11.0 27 8.1 28 0.6* 28 2.5* 27 23.6 28 1.5 29 15.7 28 12.8 29 5.3 29 7.1 29 4.3 29 6.1 30 20.3* 30 10.0 30 11.8 30 9.0 30 10.8 31 14.7 31 13.7 Jul 1 15.5 Aug 1 17.3 Sep 1 19.2 Oct 1 16.4 Nov 1 18.2 Dec 1 15.4 2 20.2 2 22.0 2 23.9* 2 21.1 2 22.9* 2 20.1* 4 0.9 4 2.7 4 4.6 4 1.7* 4 3.6* 4 0.7* 5 5.6 5 7.4 5 9.3 5 6.4 5 8.3 5 5.4 6 10.3 6 12.1 6 14.0 6 11.1 6 13.0 6 10.1 7 14.9 7 16.8 7 18.6 7 15.8 7 17.6 7 14.8 8 19.6 8 21.5 8 23.3* 8 20.5 8 22.3* 8 19.5* 10 0.3 10 2.2 10 4.0 10 1.2* 10 3.0* 10 0.2* 11 5.0 11 6.9 11 8.7 11 5.9 11 7.7 11 4.9* 12 9.7 12 11.5 12 13.4 12 10.5 12 12.4 12 9.5 13 14.4 13 16.2 13 18.1 13 15.2 13 17.1 13 14.2 14 19.1 14 20.9 14 22.8* 14 19.9 14 21.8* 14 18.9 15 23.8 16 1.6* 16 3.4 16 0.6* 16 2.4* 15 23.6* 17 4.4 17 6.3 17 8.1 17 5.3 17 7.1 17 4.3* 18 9.1 18 11.0 18 12.8 18 10.0 18 11.8 18 9.0 19 13.8 19 15.7 19 17.5 19 14.7 19 16.5 19 13.7 20 18.5 20 20.3 20 22.2* 20 19.3 20 21.2* 20 18.4 21 23.2 22 1.0* 22 2.9 22 0.0* 22 1.9* 21 23.0* 23 3.9 23 5.7 23 7.6 23 4.7 23 6.6 23 3.7* 24 8.5 24 10.4 24 12.2 24 9.4 24 11.3 24 8.4 25 13.2 25 15.1 25 16.9 25 14.1 25 15.9 25 13.1 26 17.9 26 19.8 26 21.6 26 18.8 26 20.8* 26 17.8 27 22.5 28 0.5* 28 2.3* 27 23.5* 28 1.3* 27 22.5* 29 3.3 29 5.1 29 7.0 29 4.2* 29 6.0 29 3.2* 30 8.0 30 9.8 30 11.7 30 8.8 30 10.7 30 7.8 31 12.7 31 14.5 31 13.5 31 12.5 Minima marked with an asterisk (*) are favourable from the British Isles, taking into account the altitude of the variable and the distance of the Sun below the horizon (based on longitude 0° and latitude 52° N).

Heliocentric times must be UTC corrected for the light–time to the Sun. To calculate this, use the program on the Computing Section website. http://britastro.org/computing/applets_dt.html

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BAA Handbook 2018 Variable Stars 101

b Persei (Algol): Magnitude 2.1 to 3.4, Duration 9.6 hours

h h h h h h

Jan 1 15.7 Feb 2 4.7 Mar 2 20.9* Apr 3 9.8 May 2 2.0 Jun 2 15.0 4 12.5 5 1.5* 5 17.7 6 6.7 4 22.8 5 11.8 7 9.4 7 22.3* 8 14.5 9 3.5 7 19.6 8 8.6 10 6.2 10 19.2 11 11.3 12 0.3 10 16.5 11 5.4 13 3.0* 13 16.0 14 8.1 14 21.1 13 13.3 14 2.2 15 23.8* 16 12.8 17 5.0 17 17.9 16 10.1 16 23.1 18 20.6* 19 9.6 20 1.8* 20 14.7 19 6.9 19 19.9 21 17.4 22 6.4 22 22.6* 23 11.6 22 3.7 22 16.7 24 14.3 25 3.2* 25 19.4 26 8.4 25 0.5 25 13.5 27 11.1 28 0.1* 28 16.2 29 5.2 27 21.4 28 10.3 30 7.9 31 13.0 30 18.2

Jul 1 7.1 Aug 1 20.1 Sep 2 9.1 Oct 1 1.3* Nov 1 14.2 Dec 3 3.2* 4 4.0 4 16.9 5 5.9 3 22.1 4 11.0 6 0.0* 7 0.8 7 13.7 8 2.7* 6 18.9 7 7.9 8 20.8 9 21.6 10 10.6 10 23.5* 9 15.7 10 4.7 11 17.7 12 18.4 13 7.4 13 20.4 12 12.5 13 1.5* 14 14.5 15 15.2 16 4.2 16 17.2 15 9.3 15 22.3* 17 11.3 18 12.0 19 1.0* 19 14.0 18 6.2 18 19.1 20 8.1 21 8.9 21 21.8 22 10.8 21 3.0* 21 15.9 23 4.9 24 5.7 24 18.7 25 7.6 23 23.8* 24 12.8 26 1.7* 27 2.5 27 15.5 28 4.4 26 20.6 27 9.6 28 22.6* 29 23.3 30 12.3 29 17.4 30 6.4 31 19.4

RS Canum Venaticorum 7.9 to 9.1, Duration 13 hours

h h h h h h

Jan 4 20.2 Feb 2 15.0 Mar 3 9.9 Apr 1 4.8 May 4 18.8 Jun 2 13.7 9 15.3 7 10.2 8 5.0 5 23.9* 9 13.9 7 8.8 14 10.5 12 5.3 13 0.2* 10 19.1 14 9.3 12 3.9 19 5.6 17 0.5* 17 19.3 15 14.2 19 4.2 16 23.1 24 0.7* 21 19.6 22 14.5 20 9.4 23 23.4 21 18.2 28 19.9 26 14.8 27 9.6 25 4.5 28 18.5 26 13.4 29 23.6* Jul 1 8.5 Aug 3 22.5 Sep 1 17.4 Oct 5 7.4 Nov 3 2.3 Dec 1 21.2 6 3.7 8 17.7 6 12.6 10 2.6 7 21.4 6 16.3 10 22.6 13 12.8 11 7.7 14 21.7 12 16.6 11 11.5 15 18.0 18 8.0 16 2.8 19 16.9 17 11.7 16 6.6 20 13.1 23 3.1 20 22.0 24 12.0 22 6.9 21 1.7* 25 8.3 27 22.3 25 17.1 29 7.2 27 2.0 25 20.9 30 3.4 30 12.3 30 16.0

VARIABLE STARS

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102 Variable Stars BAA Handbook 2018

MIRA STARSApproximate dates of maxima and minima for Mira stars on the programme of the BAA Variable Star Sec-tion, together with (usually) the mean visual range, period, and fraction of the period taken in rising from minimum to maximum for each star. The predictions, which are subject to inevitable uncertainty, use data from the American Association of Variable Star Observers.

Star Range Period Max–Min Date of Max. Date of Min. Max Min Period d

R And 6.9 14.3 409 0.38 Jul./Aug. Feb./Mar. W And 7.4 13.7 396 0.42 Feb./Mar. Oct. RW And 8.7 14.8 430 0.36 - Sep./Oct. R Aqr 6.5 10.3 387 0.42 Jun./Jul. Jan.R Aql 6.1 11.5 284 0.42 Aug. Apr. UV Aur* 7.4 10.6 394 0.50 Sep./Oct. Apr./May V Cam 9.9 15.4 522 0.31 2018 Dec./2019 Jan. Jul./Aug. X Cam 8.1 12.6 144 0.49 Feb.,Jul., Nov./Dec. Apr./May, Sep.SU Cnc* 10.5 [15.4 187 0.43 Feb.,Aug. May/Jun., Nov./Dec.U CVn 9.9 14.6 346 0.37 Jul. Mar.RT CVn* 9.9 [15.0 254 0.45 May Jan./Feb., Sep./Oct.S Cas 9.7 14.8 612 0.43 - Jun. T Cas 7.9 11.9 445 0.56 Jun./Jul. - ο Cet 3.4 9.3 332 0.38 Jan., Nov./Dec. Jul./Aug. R Com 8.5 14.2 363 0.38 Aug. Mar./Apr. S CrB 7.3 12.9 360 0.35 Aug. Apr. V CrB 7.5 11.0 358 0.41 Oct. May W CrB 8.5 13.5 238 0.45 Jul. Mar./Apr., Nov.R Cyg 7.5 13.9 426 0.35 May - S Cyg 10.3 16.0 323 0.50 Aug. Mar. V Cyg 9.1 12.8 421 0.46 Apr./May Dec. χ Cyg 5.2 13.4 408 0.41 Dec. Jun./Jul. T Dra 9.6 12.3 422 0.44 Jul./Aug. Jan./Feb. RU Her 8.0 13.7 485 0.43 - Jun. SS Her 9.2 12.4 107 0.48 Jan./Feb., May, Mar./Apr, Jul., Aug./Sep., Oct./Nov. 2018 Dec./2019 Jan. R Hya 4.5 9.5 389 0.49 Oct. Apr. SU Lac* 10.3 [15.0 302 0.40 Sep./Oct. May/Jun. RS Leo* 9.7 [15.5 208 0.31 Jun./Jul. Apr./May, Nov./Dec.W Lyn 9.9 ≈15 295 0.40 May Jan., Oct./Nov.X Lyn 10.2 ≈15 321 0.40 May/Jun. Jan., Nov./Dec.X Oph 6.8 8.8 329 0.53 Mar./Apr. Aug./Sep. U Ori 6.3 12.0 368 0.38 Apr./May Dec. R Ser 6.9 13.4 356 0.41 Jun./Jul. Jan./Feb. T UMa 7.7 12.9 257 0.41 Feb., Oct./Nov. Jul.

* Extreme range is given [ Fainter than

≈ Approximately

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BAA Handbook 2018 Variable Stars 103

VARIABLE STAR OF THE YEAR

Variable Star of the Year – VV CepheiVV Cep is a red supergiant star that varies in an irregular/semi-regular manner over a small range (roughly 4.9 to 5.4 in V but a little fainter visually due to its red colour) but also at 20 year intervals eclipses a fainter blue companion. The blue star is at magnitude 7.0V and is normally 1.7 magnitude fainter than the red star in V so the eclipse depth is only 0.2 magnitude in V. In B however the eclipse depth is much greater in the order of 0.8 magnitude due to the components being roughly equal in brightness. VV Cep is the brightest eclipsing binary to contain a red supergiant star and also has one of the longest known orbital periods. The mid-point of the next eclipse is in June 2018 with the eclipse due to commence in August 2017.

Spectra taken by Cannon in 1907 & 1908 indicated HD208816 to be a Mira star candidate but examination of photographic plates revealed only a limited variation range of 0.5 magnitude. Visual observations by Wendell in 1908 found an even smaller range in the order of 0.25 magnitude. Although clearly not a Mira HD208816 received the official variable star designation of VV Cep in 1925. Following more striking variation noted by McLaughlin in 1936 Sergei Gaposchkin reviewed historical photometric, spectroscopic & radial velocity data which revealed the long term eclipsing nature of VV Cep. Eclipses had been recorded in 1896, 1916 & 1936 and Gaposchkin calculated the interval to be 7430 days with an eclipse duration of 490 days (450 days for totality). The photographic data showed a consistent eclipse depth of 0.8 magnitude but in visual light the corresponding drop was only 0.1 magnitude. Gaposchkin interpreted that the binary system consisted of two stars: 1) red com-ponent: 5.7vis, 7.4pg; and 2) blue component: 7.4vis, 7.3pg; and the eclipse occurred when the blue component was obscured by the red component. Both stars were super-massive giants and Gaposchkin’s basic assessment of the system stands true today.

There were eclipses observed in 1956-57, 1977-78 and 1997-98 and the physical parameters of the system have been refined to the following: Both components are roughly 20 solar masses but that is where their similarities end. The cool red supergiant is spectral class M2Iab, between 1000-1800 solar radii in size and with a temperature of 3800K. The hot blue star is spectral class B0-B2V and is much smaller at 13-25 solar radii with a temperature of 25000K. The binary components are on average 25AU apart which is too great for significant mass transfer but there is wind interac-tion causing an accretion disk around the blue star. The system is 4900 light years distant.

The next eclipse is predicted to be: 4 August 2017 : Eclipse commences

27 October 2017 : Totality commences1 June 2018 : Mid eclipse

6 February 2019 : Totality ends16 May 2019 : Eclipse ends

The accompanying light curve (50 day means) compiled from NWAVSO visual observations illustrate the shal-low (0.2 magnitude) fade recorded during the 1977-78 eclipse which appeared to last 650 days. The accompany-ing chart includes a sequence for visual observers to use to monitor the variation of the red supergiant in addition to the smaller variation caused by the eclipse of the blue star.

Due to its small range of variation VV Cep is more suited to DSLR and CCD camera work especially in U and B. Recommended comparison stars are (both identified on the chart):

20 Cep: U=8.46, B=6.68, V=5.2719 Cep: U=4.33, B=5.17, V=5.11 (also labelled as comparison C)

Measurements prior to and after the eclipse that show the variations outside of the eclipse will help to interpret any variation recorded during the eclipse.

Spectroscopic measurements outside of and during the eclipse are also encouraged and will help in particular in interpreting the physics of the accretion disk around the blue star. Useful guidance on undertaking spectroscopy of VV Cep is given in the web-page referenced below.

VV Cep lies in a rich Milky Way field occupying a central position within the diamond of Cepheus and at nearly 64 degrees north it is circumpolar from the British Isles.

An international campaign has been launched to study the 2017-2019 eclipse of VV Cep and details can be found here:

http://www.ap.smu.ca/~pbennett/vvcep/campaign2017.html

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104 Variable Stars BAA Handbook 2018

VV

CE

PHE

I L

IGH

T C

UR

VE

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BAA Handbook 2018 Variable Stars 105

VV CEPHEI FINDER CHART

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106 Double Stars BAA Handbook 2018

EPHEMERIDES OF VISUAL BINARY STARSInspection of the two–point ephemeris will indicate whether a pair is closing, relatively static, or opening up, and whether motion is direct or retrograde. A fast–mover of long period is probably near periastron, while a slow–mover of short period is likely to be near apastron. The orbital ele-ments employed for the computation are those published in the Sixth Catalog of Orbits of Visual Binary Stars, by William I. Hartkopf and Brian D. Mason, U.S. Naval Observatory:

http://ad.usno.navy.mil/wds/orb6.html

2000.0 2018.0 2019.0Star Name ADS RA Dec. Mags. Period PA Dist. PA Dist. h m ° ′ y ° ″ ° ″85 Peg 17175 0 02.2 +27 05 5.8 8.9 26 98.7 0.60 112.2 0.70OΣ 4 221 0 16.7 +36 29 7.9 9.8 109 358.3 0.16 345.5 0.16λ Cas 434 0 31.8 +54 31 5.3 5.6 246 236.5 0.14 243.6 0.13β 395 520 0 37.3 –24 46 6.6 6.2 25 118.5 0.60 122.8 0.48η Cas 671 0 49.1 +57 49 3.5 7.3 479 325.5 13.35 325.9 13.38 36 And 755 0 55.0 +23 38 6.1 6.5 168 332.5 1.15 333.5 1.17Howe 4 1223 1 33.7 –12 13 9.2 9.3 146 330.5 0.93 330.3 0.93Dunlop 5 … 1 39.8 –56 12 5.7 5.9 475 186.4 11.62 186.1 11.63Σ 186 1538 1 55.9 +01 51 6.7 6.8 166 72.8 0.69 73.7 0.67α Psc 1615 2 02.0 +02 46 4.1 5.1 3267 261.5 1.84 260.8 1.84 10 Ari 1631 2 03.7 +25 56 5.8 7.8 325 348.1 1.54 348.5 1.55Σ 228 1709 2 14.0 +47 29 6.5 7.2 145 304.5 0.64 306.6 0.61h 3494 .. 2 19.8 –35 27 9.0 9.1 475 241.4 2.30 240.9 2.31ι Cas AB 1860 2 29.1 +67 24 4.6 6.9 620 227.6 2.63 227.5 2.63Σ 305 2122 2 47.5 +19 22 7.5 8.2 531 307.0 3.60 306.9 3.60 α For 2402 3 12.1 –28 59 3.9 7.1 269 300.6 5.42 300.6 5.43Σ 367 2416 3 14.0 +00 44 8.1 8.1 753 130.0 1.25 129.6 1.257 Tau 2616 3 34.4 +24 28 6.6 6.8 522 350.8 0.76 350.5 0.76OΣ 65 2799 3 50.3 +25 35 5.7 6.5 61 202.1 0.50 202.4 0.5340 Eri BC 3093 4 15.3 –07 39 10.0 11.4 224 330.9 8.02 330.6 7.94 OΣ 77 AB 3082 4 15.9 +31 42 8.0 8.2 188 303.9 0.49 305.2 0.49Hu 445 3614 5 01.7 +20 50 9.3 8.4 166 152.8 0.35 155.1 0.3414 Ori 3711 5 07.9 +08 30 5.7 6.6 197 286.1 0.97 284.6 0.98η Gem 4841 6 14.9 +22 30 3.5 6.1 474 252.0 1.61 251.8 1.61OΣ 149 5234 6 36.4 +27 17 7.1 8.9 119 279.7 0.74 278.7 0.73 12 Lyn AB 5400 6 46.2 +59 27 5.4 6.0 908 65.8 1.91 65.5 1.911 Lyn 5514 6 53.1 +59 27 6.0 6.5 316 354.3 0.30 356.1 0.31α Gem 6175 7 34.6 +31 53 1.9 2.9 460 53.2 5.25 52.7 5.319 Pup 6420 7 51.8 –13 54 5.6 6.4 23 300.9 0.48 303.8 0.44ζ Cnc AB 6650 8 12.2 +17 39 4.9 5.8 1115 10.2 1.13 7.0 1.13 ζ Cnc AB–C 6650 8 12.2 +17 39 6.2 7.1 1115 65.0 5.93 64.5 5.93β 208 6914 8 39.1 –22 40 5.3 6.8 123 58.4 0.51 62.7 0.45I 314 .. 8 39.4 –36 36 6.4 7.9 67 241.4 0.86 241.1 0.88δ Vel .. 8 44.7 –54 43 1.9 5.5 147 208.5 0.61 203.0 0.69ε Hya AB–C 6993 8 46.8 +06 25 3.5 5.0 15 309.1 2.82 309.9 2.82 Σ 1338 7307 9 21.0 +38 11 6.7 7.0 303 318.3 1.00 320.1 1.00ω Leo 7390 9 28.5 +09 03 5.6 7.2 118 112.7 0.86 113.7 0.87γ Sex 7555 9 52.5 –08 06 5.4 6.4 78 39.2 0.51 37.7 0.49γ Leo 7724 10 20.0 +19 50 2.3 3.6 554 127.3 4.74 127.4 4.75β 411 7846 10 36.1 –26 41 6.6 7.7 159 303.7 1.33 303.3 1.33

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BAA Handbook 2018 Double Stars 107

ξ UMa AB 8119 11 18.2 +31 32 4.3 4.8 60 161.0 2.01 156.6 2.10ι Leo 8148 11 23.9 +10 32 4.0 6.7 186 93.5 2.18 92.7 2.20BrsO 5 .. 11 24.7 –61 39 7.6 8.7 399 248.7 7.63 249.0 7.67OΣ 235 8197 11 32.3 +61 05 5.6 7.5 73 42.0 0.93 44.3 0.95Σ 1639 8539 12 24.4 +25 35 6.7 7.8 575 322.8 1.85 322.8 1.85 β 28 8573 12 30.1 –13 24 6.4 9.5 151 347.9 2.14 348.5 2.14γ Cen .. 12 41.5 –48 58 2.8 2.9 84 47.9 0.21 35.2 0.30γ Vir 8630 12 41.7 –01 27 3.4 3.5 169 0.3 2.69 358.8 2.8135 Com 8695 12 53.3 +21 15 5.1 7.0 539 200.1 1.18 200.9 1.18I 83 .. 12 56.7 –47 41 7.3 7.6 173 236.5 0.86 236.8 0.86 78 UMa 8739 13 00.7 +56 22 5.0 7.8 105 135.3 0.68 142.6 0.63A1609 AB 8901 13 25.8 +44 30 9.4 8.7 44 68.8 0.32 75.9 0.2925 CVn 8974 13 37.5 +36 18 4.9 6.9 228 94.2 1.67 93.9 1.67α Cen .. 14 39.6 –60 50 0.0 1.3 80 326.9 4.46 337.1 4.92ζ Boo 9343 14 41.1 +13 44 4.4 4.5 125 285.7 0.33 283.3 0.29 φ309 .. 14 46.2 –21 11 7.3 7.3 13 170.2 0.22 186.9 0.17ξ Boo 9413 14 51.4 +19 06 4.7 6.9 152 299.1 5.39 297.8 5.30OΣ 288 9425 14 53.4 +15 42 6.8 7.5 313 156.8 0.97 156.2 0.96H 4707 .. 14 54.2 –66 25 7.5 8.0 346 267.3 1.24 266.7 1.2644 Boo 9494 15 03.8 +47 39 5.2 6.1 210 79.9 0.53 90.6 0.39 η CrB 9617 15 23.2 +30 17 5.6 5.9 41 237.8 0.46 256.0 0.39γ Lup .. 15 35.1 –41 10 2.9 4.4 190 276.2 0.82 276.1 0.82π2 UMi 9769 15 39.6 +79 59 7.3 8.1 172 21.1 0.61 20.9 0.61ξ Sco AB 9909 16 04.4 –11 22 5.1 4.8 46 8.6 1.11 10.0 1.12σ CrB AB 9979 16 14.7 +33 52 6.1 6.5 136 238.6 7.23 238.7 7.24 λ Oph 10087 16 30.9 +01 59 4.1 5.1 129 43.5 1.41 44.4 1.41ζ Her 10157 16 41.3 +31 36 2.9 5.4 34 117.7 1.32 111.7 1.3620 Dra 10279 16 56.4 +65 02 7.0 7.3 422 66.4 1.14 66.3 1.14MlbO 4 AB .. 17 19.0 –34 59 6.3 7.3 42 80.0 0.53 22.8 0.52BrsO 13 .. 17 19.1 –46 38 5.6 8.8 953 258.4 10.62 258.6 10.69 26 Dra 10660 17 35.0 +61 53 5.2 8.5 76 231.1 0.32 207.7 0.36τ Oph 11005 18 03.1 –08 11 5.2 5.8 257 288.3 1.51 288.8 1.4970 Oph 11046 18 05.5 +02 30 4.2 6.1 88 123.4 6.50 122.5 6.56h 5014 .. 18 06.8 –43 25 5.6 5.6 450 358.6 1.74 358.1 1.74OΣ 358 11483 18 35.9 +16 59 6.9 7.0 380 144.7 1.49 144.2 1.49 ε1 Lyr AB 11635 18 44.3 +39 40 5.1 6.1 1725 345.0 2.32 344.7 2.31ε2 Lyr CD 11635 18 44.3 +39 40 5.2 5.3 724 74.8 2.39 74.4 2.40γ CrA .. 19 06.4 –37 04 4.5 6.4 122 336.5 1.46 332.4 1.48δ Cyg 12880 19 45.0 +45 08 2.8 6.2 918 216.0 2.75 215.6 2.76λ Cyg 14296 20 47.4 +36 29 4.7 6.2 391 358.3 0.92 357.9 0.92 4 Aqr 14360 20 51.4 –05 38 6.4 7.4 200 31.8 0.74 32.6 0.73ε Equ AB 14499 20 59.1 +04 18 5.9 6.3 101 273.8 0.06 139.7 0.02τ Cyg 14787 21 14.8 +38 03 3.8 6.5 50 192.0 0.98 187.8 0.99μ Cyg 15270 21 44.1 +28 45 4.7 6.1 789 324.2 1.50 325.3 1.4853 Aqr 15934 22 26.6 –16 45 6.2 6.3 3500 73.5 1.30 77.6 1.32 Kr 60 15972 22 28.0 +57 42 9.9 11.4 45 244.4 1.60 229.6 1.73ζ Aqr AB 15971 22 28.8 –00 01 4.3 4.4 487 157.4 2.24 156.2 2.26π Cep 16538 23 07.9 +75 23 4.6 6.8 163 1.8 1.12 2.6 1.12β 80 16665 23 18.9 +05 24 8.1 9.3 97 249.9 0.78 251.8 0.8172 Peg 16836 23 34.0 +31 20 5.6 6.1 492 105.8 0.58 106.5 0.58

EPHEMERIDES OF VISUAL BINARY STARS 2000.0 2018.0 2019.0Star Name ADS RA Dec. Mags. Period PA Dist. PA Dist. h m ° ′ y ° ″ ° ″

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108 Bright Stars BAA Handbook 2018

BRIGHT STARSFOR EPOCH 2018.5

Name RA Dec. V Name RA Dec. Vh m s ° ' " h m s ° ' "

α And 0 09 20.9 +29 11 33 2.07 α UMa 11 04 51.2 +61 39 03 1.81β Cas* 0 10 10.6 +59 15 06 2.28 β Leo 11 15 05.4 +20 25 19 2.56α Cas 0 41 34.1 +56 38 19 2.24 α Cru† 12 27 38.5 –63 12 05 0.77β Cet 0 44 31.0 –17 53 07 2.04 γ Cru* 12 32 12.2 –57 13 00 1.59β And 1 10 46.4 +35 43 05 2.07 γ Cen† 12 42 32.8 –49 03 40 2.20

α Eri 1 38 24.0 –57 08 36 0.45 β Cru* 12 48 48.9 –59 47 22 1.25γ And 2 05 02.6 +42 25 03 2.10 ε UMa* 12 54 50.3 +55 51 35 1.76α Ari 2 08 13.2 +23 32 57 2.01 ζ UMa 13 24 40.1 +54 49 45 2.23α UMi* 2 55 00.0 +89 20 31 1.97 α Vir* 13 26 10.2 –11 15 26 0.98α Per* 3 09 22.8 +41 01 32 2.09 ε Cen 13 41 04.3 –53 33 35 2.29

α Per 3 25 39.2 +49 55 32 1.79 η UMa 13 48 16.1 +49 13 17 1.85η Tau 3 48 35.3 +24 09 40 2.85 β Cen* 14 05 08.7 –60 27 41 0.61α Tau 4 36 59.1 +16 32 42 0.87 θ Cen 14 07 46.7 –36 27 36 2.06β Ori 5 15 25.7 –08 10 54 0.18 α Boo 14 16 30.3 +19 05 12 –0.05α Aur* 5 18 03.5 +46 00 53 0.08 η Cen* 14 36 41.4 –42 14 17 2.33

γ Ori 5 26 07.5 +06 21 54 1.64 α Cen cg* 14 40 52.3 –60 54 42 –0.01β Tau 5 27 27.8 +28 37 17 1.65 α Lup* 14 43 10.1 –47 27 59 2.30δ Ori* 5 32 57.2 +00 17 12 2.25 ε Boo 14 45 47.7 +26 59 49 2.35ε Ori 5 37 09.2 –01 11 29 1.69 β UMi 14 50 40.2 +74 04 47 2.07ζ Ori 5 41 41.6 –01 56 03 1.74 α CrB* 15 35 28.3 +26 39 12 2.22

κ Ori 5 48 38.1 –09 39 52 2.07 δ Sco 16 01 25.8 –22 40 23 2.29α Ori* 5 56 10.4 +07 24 33 0.45 α Sco* 16 30 32.7 –26 28 18 1.06β Aur* 6 00 53.2 +44 56 50 1.90 α TrA 16 50 38.4 –69 03 32 1.91β CMa* 6 23 30.9 –17 57 59 1.98 ε Sco 16 51 21.9 –34 19 31 2.29α Car* 6 24 21.8 –52 42 23 –0.62 λ Sco* 17 34 52.0 –37 06 56 1.62

γ Gem 6 38 46.8 +16 22 54 1.93 α Oph 17 35 47.6 +12 32 52 2.08α CMa 6 45 57.4 –16 44 35 –1.44 θ Sco 17 38 39.0 –43 00 28 1.86ε CMa 6 59 21.2 –28 59 54 1.50 γ Dra 17 57 02.2 +51 29 14 2.24δ CMa 7 09 08.6 –26 25 25 1.83 ε Sgr 18 25 24.0 –34 22 27 1.79α Gem† 7 35 46.4 +31 50 44 1.58 α Lyr 18 37 33.9 +38 48 07 0.03

α CMi 7 40 16.3 +05 10 33 0.40 σ Sgr 18 56 24.7 –26 16 20 2.05β Gem 7 46 26.7 +27 58 48 1.16 β Cyg† 19 31 28.1 +27 59 58 3.05ζ Pup 8 04 14.1 –40 03 22 2.21 α Aql 19 51 41.1 +8 55 06 0.76γ Vel* 8 10 06.2 –47 23 30 1.75 γ Cyg 20 22 53.6 +40 19 00 2.23ε Car* 8 22 53.5 –59 34 10 1.86 α Pav 20 27 06.0 –56 40 27 1.94

δ Vel 8 45 12.9 –54 46 38 1.93 α Cyg 20 42 03.8 +45 20 50 1.25λ Vel* 9 08 40.7 –43 30 29 2.23 α Cep 21 19 01.2 +62 39 52 2.45β Car 9 13 23.7 –69 47 37 1.67 ε Peg* 21 45 05.7 +09 57 38 2.38ι Car* 9 17 35.1 –59 21 12 2.21 β Gru 22 09 23.4 –46 52 14 1.73α Hya 9 28 29.8 –08 44 23 1.99 α Gru* 22 43 45.8 –46 47 14 2.07

α Leo 10 09 21.3 +11 52 34 1.36 α PsA 22 58 40.1 –29 31 26 1.17γ Leo† 10 20 59.4 +19 44 50 2.01 β Peg* 23 04 40.4 +28 11 00 2.44β UMa 11 02 56.8 +56 16 58 2.34 α Peg 23 05 41.0 +15 18 18 2.49

* = Variable star † = Double star

Note: double star co–ordinates refer to the brighter component, but magnitude refers to the combined light.

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BAA Handbook 2018 Active Galaxies 109

ACTIVE GALAXIES

Object RA Dec. Const. Type V* U.2000 (2000.0) Chart No. h m °3C 66A 2 22 +43.0 And BL Lac 14.0 – 16.3 62NGC 1275 3 20 +41.5 Per Seyfert 13.2 – 13.7 633C 120 (BW Tau) 4 33 +05.4 Tau BL Lac 13.7 – 14.6 178S5 0716+71 7 22 +71.3 Cam BL Lac 12.3 – 15.3 21OJ+287 8 54 +20.1 Cnc BL Lac 12.4 – 16.0 142Markarian 421 11 04 +38.2 UMa BL Lac 12.3 – 14.2 106NGC 4151 12 10 +39.4 CVn Seyfert 11.0 – 12.4 74W Comae 12 21 +28.2 Com BL Lac 11.5 – 16.0 1483C 273 12 26 +02.3 Vir Quasar 12.3 – 13.3 2383C 279 12 56 –05.8 Vir Quasar 11.5 – 17.0 239BL Lacertae 22 02 +42.3 Lac BL Lac 12.5 – 15.5 87

*Approximate range

FINDER CHARTS FOR ACTIVE GALAXIES

Charts for all of the active galaxies listed above have been included in previous BAA Handbooks and are listed below. Object BAA VSS Chart Handbook Year 3C 66A 309.01 2010 NGC1275 296.01 2008 BW Tau 320.01 2011 S5 0716+71 310.01 2009 OJ+287 208.02 2004 Markarian 421 243.01 2001 NGC4151 297.01 2007 W Com 148.03 2002 3C 273 244.01 2003 3C 279 151.02 2006 BL Lac 242.01 2005 Direct links to individual BAA VSS charts for the Active Galaxies can be found in a more detailed table of these galaxies, on the Computing Section website at:

http://britastro.org/computing/handbooks_active.html

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110 Time BAA Handbook 2018

TIMEUniversal Time (UT, Greenwich Mean Time beginning at midnight) is used generally throughout the Handbook.

Terrestrial Time (TT) is the uniform time system used in computing the ephemerides of the bodies of the Solar System. TT is currently ahead of UT by a small amount ΔT which must be determined by observations; thus

TT = UT + ΔTThe value of ΔT for July 2018 is estimated to be about 70.4 seconds.

Greenwich Mean Astronomical Time (GMAT), or Greenwich Mean Time beginning at noon, was in use before 1925 January 1, and many astronomical records prior to that date are referred to this system. To convert UT to GMAT subtract 12 hours, and to convert GMAT to UT add 12 hours.

Greenwich Sidereal Time (GST) is given in the table below at 0h UT. It may be obtained with sufficient accuracy for setting the circles of a telescope at any other time by adding 3.94 minutes for every complete day after a tabulated date, together with the correction, ΔT, for parts of a day from the table which follows:

For greater accuracy (±0.2S) use the equation : GST (at 0h UT) = '6.640906h + 0.06570982h dwhere d is the number of days from January 0.

The tabulated sidereal time is actually the mean sidereal time. The difference between mean and apparent sidereal time is never more than about 1.2 seconds.Local Sidereal Time (LST) and Local Hour Angle (LHA) are found from LST = GST + λ LHA = LST – RAWhere λ is the longitude, expressed in time, measured positive eastwards from Greenwich.

The Julian Date, in which the day begins at noon, is used in accurate computing work and is given in the table on p.111.

The Sun’s Longitude is used as a measure of time in meteor work. It may be interpolated from the table on p.111.

Time ΔT Time ΔT Time ΔT Time ΔT h m h m h m h m 0 00.0 m 5 46.9 m 11 52.2 m 17 57.4 m 0.0 1.0 2.0 3.0 0 18.2 6 23.5 12 28.7 18 33.9 0.1 1.1 2.1 3.1 0 54.7 7 00.0 13 05.3 19 10.5 0.2 1.2 2.2 3.2 1 31.3 7 36.5 13 41.7 19 47.0 0.3 1.3 2.3 3.3 2 07.8 8 13.0 14 18.3 20 23.5 0.4 1.4 2.4 3.4 2 44.3 8 49.6 14 54.8 21 00.0 0.5 1.5 2.5 3.5 3 20.8 9 26.1 15 31.3 21 36.6 0.6 1.6 2.6 3.6 3 57.4 10 02.6 16 07.8 22 13.1 0.7 1.7 2.7 3.7 4 33.9 10 39.1 16 44.4 22 49.6 0.8 1.8 2.8 3.8 5 10.4 11 15.6 17 20.9 23 26.1 0.9 1.9 2.9 3.9

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BAA Handbook 2018 Time 111

TIME Julian Sun's Long. Julian Sun's Long.2018 Date GST 2000.0 2018 Date GST 2000.0 2458 h m ° 2458 h m °Dec 29 116.5 6 30.57 277.21 Jul. 2 301.5 18 39.95 99.84 5.09 4.76Jan. 3 121.5 6 50.28 282.30 7 306.5 18 59.66 104.60 5.10 4.77 8 126.5 7 09.10 287.40 12 311.5 19 19.37 109.37 5.09 4.77 13 131.5 7 29.71 292.49 17 316.5 19 39.09 114.14 5.10 4.77 18 136.5 7 49.42 297.59 22 321.5 19 58.80 118.91 5.09 4.78 23 141.5 8 09.13 302.68 27 326.5 20 18.51 123.69 5.08 4.77 28 146.5 8 28.85 307.76 Aug. 1 300.5 18 38.23 128.46 5.07 4.79Feb. 2 151.5 8 48.56 312.83 6 336.5 20 57.94 133.25 5.07 4.79 7 156.5 9 08.27 317.90 11 341.5 21 17.65 138.04 5.06 4.81 12 161.5 9 27.99 322.96 16 346.5 21 37.36 142.85 5.06 4.81 17 166.5 9 47.70 328.02 21 351.5 21 57.08 147.66 5.04 4.81 22 171.5 10 07.41 333.06 26 356.5 22 16.79 152.47 5.03 4.83 27 176.5 10 27.12 338.09 31 361.5 22 36.50 157.30 5.02 4.84Mar. 4 181.5 10 46.84 343.11 Sep. 5 366.5 22 56.22 162.14 5.00 4.85 9 186.5 11 06.55 348.11 10 371.5 23 15.93 166.99 5.00 4.87 14 191.5 11 26.26 353.11 15 376.5 23 35.64 171.86 4.98 4.88 19 196.5 11 45.98 358.09 20 381.5 23 55.36 176.74 4.96 4.89 24 201.5 12 05.69 3.05 25 386.5 0 15.07 181.63 4.95 4.90 29 206.5 12 25.40 8.00 30 391.5 0 34.78 186.53 4.94 4.92Apr. 3 211.5 12 45.12 12.94 Oct. 5 396.5 0 54.49 191.45 4.92 4.93 8 216.5 13 04.83 17.86 10 401.5 1 14.21 196.38 4.91 4.95 13 221.5 13 24.54 22.77 15 406.5 1 33.92 201.33 4.90 4.96 18 226.5 13 44.25 27.67 20 411.5 1 53.63 206.29 4.88 4.98 23 231.5 14 03.97 32.55 25 416.5 2 13.35 211.27 4.87 4.98 28 236.5 14 23.68 37.42 30 421.5 2 33.06 216.25 4.85 5.01May 3 241.5 14 43.39 42.27 Nov. 4 426.5 2 52.77 221.26 4.85 5.01 8 246.5 15 03.11 47.12 9 431.5 3 12.48 226.27 4.83 5.03 13 251.5 15 22.82 51.95 14 436.5 3 32.20 231.30 4.82 5.04 18 256.5 15 42.53 56.77 19 441.5 3 51.91 236.34 4.82 5.05 23 261.5 16 02.24 61.59 24 446.5 4 11.62 241.39 4.80 5.05 28 266.5 16 21.96 66.39 29 451.5 4 31.34 246.44 4.79 5.07Jun. 2 271.5 16 41.67 71.18 Dec. 4 456.5 4 51.05 251.51 4.79 5.08 7 276.5 17 01.38 75.97 9 461.5 5 10.76 256.59 4.78 5.08 12 281.5 17 21.10 80.75 14 466.5 5 30.48 261.67 4.78 5.09 17 286.5 17 40.81 85.53 19 471.5 5 50.19 266.76 4.77 5.09 22 291.5 18 00.52 90.30 24 476.5 6 09.90 271.85 4.77 5.09 27 296.5 18 20.24 95.07 29 481.5 6 29.61 276.94 4.77

The precession in longitude from 2000.0 to 2018.0 is +0.25° and from 2000.0 to 1950.0 is –0.70°.

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112 Astronomical and Physical Constants BAA Handbook 2018

ASTRONOMICAL AND PHYSICAL CONSTANTS

Gaussian gravitational constant 0.01720209895Astronomical unit (au) 149,597,870,700 metresSpeed of light in vacuo 299,792.458 km s–1

Dynamical form–factor J2 for the Earth 0.001082636Product of gravitational constant and mass of the Earth 398,600.5 km3 s–2

Earth–Moon mass ratio 81.3006Moon’s sidereal mean motion 2.661699489x10–6 radians s–1 = 0.5490149294" s–1

Obliquity of the ecliptic (2000) 23° 26' 21.448"Constant of nutation in obliquity (2000) 9.2052331"Solar parallax 8.794143"Light–time for unit distance 499.004784 s = 0.005775518 dConstant of aberration 20.49551"Mean distance Earth to Moon 384,400 kmConstant of sine Moon’s parallax 3422.451"Lunar inequality 6.43987"Parallactic inequality 124.986"Length of the year: Tropical (equinox to equinox) 365.24219d

Sidereal (fixed star to fixed star) 365.25636d

Anomalistic (apse to apse) 365.25964d

Eclipse (Moon’s node to Moon’s node) 346.62003d

Gaussian (Kepler’s law for a = 1) 365.25690d

Length of the month: Tropical (equinox to equinox) 27.32158d

Sidereal (fixed star to fixed star) 27.32166d

Anomalistic (apse to apse) 27.55455d

Draconic (node to node) 27.21222d

Synodic (New Moon to New Moon) 29.53059d

Length of the day: Mean solar day 24h 03m 56.555s = 1.00273791d mean sidereal time Mean sidereal day 23h 56m 04.091s = 0.99726957d mean solar time Sidereal rotation period of the Earth 23h 56m 04.099s = 0.99726966d mean solar timeSolar radiation: Solar constant 1.366 x 103 J m–2 s–1

Radiation emitted 3.84 x 1026 J s–1

Radiation emittance at surface 6.32 x 107 J m–2 s–1

Total internal radiant energy 2.8 x 1040 J Radiation emitted per unit mass 1.932 x 10–4 J s–1 kg–1

Visual absolute magnitude (Mv) +4.82 Colour indices (B–V, U–B) +0.65, +0.19 Spectral type G2V Effective temperature 5,800 K

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BAA Handbook 2018 Astronomical and Physical Constants 113

The Galaxy: Pole of galactic plane (2000) 12h 51m 26.28s, δ +27° 07' 42.0" Point of zero longitude (2000) 17h 45m 37.22s, δ –28° 56' 10.2" Galactic Longitude of North Celestial Pole (2000) 122.93° Mass 1.1 x 1011 solar masses = 2.2 x 1041 kg Average density 0.1 solar mass pc–3 = 7 x 10–21 kg m–3

Diameter 25,000 pc Thickness 4,000 pc Distance of Sun from centre 8,200 pc Distance of Sun above galactic plane 24 ±6 pc Solar apex (2000) (from radio astronomy) RA 18h 03.8m , Dec. 30° 00' Solar motion (from bright stars) 19.7 km s–1

Period of revolution of Sun about centre 2.2 x 108 yrConversion factors: Light–year (ly) 9.4607 x 1012 km = 63,240 au = 0.30660 pc Parsec (pc) 30.857 x 1012 km = 206,265 au = 3.2616 lyFigure of the Earth: Equatorial radius 6,378,136.6 m Polar radius 6,356,751.9 m Flattening 0.0033528197 * ρ sin φ' = S sin φ, ρ cos φ' = C cos φ where: S = 0.99497418 – 0.00167082 cos 2φ +10–8 (210 cos 4φ + 15.7 h) C = 1.00167997 – 0.00168208 cos 2φ +10–8 (212 cos 4φ + 15.7 h) ρ = 0.99832707 + 0.00167644 cos 2φ –10–8 (352 cos 4φ – 15.7 h) + 10–8 cos 6φ tan φ' = [0.9933054 + (0.11 x 10–8 h)] tan φ φ – φ' = 692.74" sin 2φ – 1.16" sin 4φ 1° of latitude = [111.1333 – 0.5598 cos 2 φ + 0.0012 cos 4φ] km 1° of longitude = [111.4133 cos φ – 0.0935 cos 3 φ + 0.0001 cos 5φ] km Acceleration due to gravity g = 9.780310 [1 + 0.00530239 sin2φ – 0.00000587 sin2 2φ – (31.55 x 10–8) h] m s–2

Length of seconds pendulum l = [0.9935769 – 0.0026272 cos 2φ + 0.0000029 cos 4φ – (3133 x 10–10) h] m

Constant of gravitation 6.67428 x 10–11 kg–1 m3 s–2

Centennial general precession p = 5028.796195" + 2.2108696" T†_______________________________________________________________________* φ = Geographic or geodetic latitude ρ = Geocentric distance in equatorial radii φ' = Geocentric latitude h = Height in metres† T = Time measured in Julian centuries from J2000.0

ASTRONOMICAL AND PHYSICAL CONSTANTS

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114 Internet Resources BAA Handbook 2018

INTERNET RESOURCESThe following internet resources may be of interest to Handbook users. Mention here does not imply that the BAA sanctions the contents of these web pages. Web addresses can change and sites may not always be available. BAA Section home pages can be accessed from the BAA home page (see back cover).

BAA Computing Section website http://britastro.org/computing

Iau Central Bureau for Astronomical Telegrams (main page)http://www.cbat.eps.harvard.edu/index.html

Astronomical data and cataloguesCentre de Données Astronomiques de Strasbourg http://cdsportal.u-strasbg.fr/

National Space Science Data Center (USA) http://nssdc.gsfc.nasa.govAstronomical Data Archives Center (Japan) http://dbc.nao.ac.jp/index.html.en

The Sun, eclipses and space weatherSOHO web site http://sohowww.nascom.nasa.govSolar Terrestrial Dispatch http://www.spacew.com

Aurorae http://www.swpc.noaa.gov/phenomena/auroraSpace Weather Prediction Center http://www.swpc.noaa.gov/forecasts

Space Weather http://www.spaceweather.comNASA Eclipse Home Page http://eclipse.gsfc.nasa.gov/eclipse.html

Eclipses and Transits http://xjubier.free.fr/en/index_en.htmlEclipse maps http://www.eclipse-maps.com/Eclipse-Maps/Welcome.html

Eclipse weather http://eclipsophile.com/

Lunar phasesLunar Terminator Visualisation Tool (LTVT) http://ltvt.wikispaces.com/LTVT+Download

Solar system bodiesJet Propulsion Laboratory HORIZONS System http://ssd.jpl.nasa.gov/?horizons

HORIZONS Web-Interface http://ssd.jpl.nasa.gov/horizons.cgiJPL HORIZONS tutorial http://ssd.jpl.nasa.gov/?horizons_tutorial

(As of 2017 August 12, access to solar-system data and highly accurate ephemerides for 737346 asteroids, 3478 comets, 178 planetary satellites, 8 planets, the Sun, L1 and L2 points, spacecraft, and system barycentres.)

Comet and meteor informationLatest IAU comet ephemerides http://www.minorplanetcenter.net/iau/Ephemerides/Comets/Weekly Information about Bright Comets http://www.aerith.net/comet/weekly/current.html

Comets http://www.cometography.comInternational Meteor Organisation http://www.imo.net

Minor planets (asteroids)IAU Minor Planet Center http://www.minorplanetcenter.org/iau/mpc.html

Lowell Observatory http://asteroid.lowell.eduSolar System Dynamics on-line Tools http://ssd.jpl.nasa.gov/?tools

Near Earth Object Confirmation page http://www.minorplanetcenter.org/iau/NEO/ToConfirm.html

Timing occultations and other dynamical eventsIOTA Europe http://www.iota-es.de/

IOTA USA and rest of world http://www.occultations.orgGeneral information http://www.lunar-occultations.com/iota/iotandx.htmEuropean asteroid occultation resource and results http://www.euraster.net

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BAA Handbook 2018 Internet Resources and Greek Alphabet 115

body. Further details INTERNET RESOURCES Recent supernovae

http://www.cbat.eps.harvard.edu/lists/RecentSupernovae.html

Variable star informationAAVSO http://www.aavso.org

BAA Variable Star Section http://www.britastro.org/vss/General Catalogue of Variable Stars http://www.sai.msu.su/gcvs/cgi-bin/search.htm

Artificial satellite visibilityHeavens Above http://www.heavens-above.com

Atmospheric phenomenahttp://www.atoptics.co.uk

Noctilucent cloud observers http://ed-co.net/nlcnet/

Equipment reviewsExcelsis http://www.excelsis.com/1.0/catalog.php?categoryid=6

Astronomical and space news Astronomy Now http://www.astronomynow.com

Sky and Telescope http://www.skyandtelescope.comESO http://www.eso.org/public/outreach

Space.com http://www.space.comNASA http://science.nasa.govESA http://www.esa.int/ESA

Science Daily http://www.sciencedaily.com/news/space_time/astronomy/

Dark SkiesBAA Commission for Dark Skies http://www.britastro.org/dark-skies

International Dark-Sky Association http://www.darksky.org

Astronomy Picture of the Dayhttp://apod.nasa.gov/apod/astropix.html

Timehttp://stjarnhimlen.se/comp/time.html

The Astronomer (main page)http://www.theastronomer.org

GREEK ALPHABET

α alpha β beta γ gamma δ delta ε epsilon ζ zeta η eta θ theta ι iota κ kappa λ lamda μ mu ν nu ξ xi ο omicron π pi ρ rho σ sigma τ tau υ upsilon φ phi χ chi ψ psi ω omega

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116 Acknowledgements & Errata BAA Handbook 2018

ERRATAHandbook 2017

p.7 Carrington Rotation Number, the value for Dec. 14.05 should be "2198" and not "2185"

ACKNOWLEDGEMENTSThe Handbook would not be possible without the work of its many data contributors : Andrew Sinclair contributed the diagrams showing the visibility of planets and their appearances and also data and diagrams for Saturn's satellites. Barry Leggett supplied data for Jovian satellite eclipses and transits. Des Loughney provided heliocentric times of primary minima of variable stars. Fred Espenak (previously of the NASA/Goddard Space Flight Center) for his Eclipse charts. John Isles contributed the data on Mira stars. John Mason provided the meteor data. John Toone provided data on active galaxies and with Gary Poyner, provided data for variable stars and for the variable star of the year. Jonathan Shanklin provided data on comets. Ken Hall provided lunar libration data. Richard Miles provided data for asteroids, near–earth objects, trans–neptunian and dwarf planets, and diagrams for Pluto. Asteroid Favourable Observing Opportunities data were prepared by him, using data from the MPCORB database by Brian D. Warner; Alan W. Harris (MoreData! Inc.); and Petr Pravec (Astronomical Institute, Ondrejov, Czech Republic). Richard Kaye provided the System III Jupiter data, using a program written by himself. Robert Mackenzie provided the start dates for Carrington rotations. Susan Stewart of the United States Naval Observatory provided the bright stars positional data. Tim Haymes provided lunar occultation data and, with Edwin Goffin and Eberhard Riedel (International Occultation Timing Association), the tables and maps for asteroid occultations and grazing lunar occultations. Mike Kretlow for use of his asteroid and TNO database of current predictions. Steve Bell (Her Majesty's Nautical Almanac Office) provided various data. Steve Preston for his global updates on asteroidoccultations.com Tony Evans provided data for Mercury, Venus and Mars. William Thuillot (Institut de Mécanique Céleste et de Calcul des Ephémérides) supplied the diagrams of Jupiter’s satellites.

Contributors have checked their own and others’ contributions and their comments have greatly improved the Handbook. The Editor gratefully acknowledges contributors’ support in answering any queries, and the many proof readers for their assistance. Any data not mentioned above have been provided by the Computing Section.

STEVE HARVEY Director

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The British Astronomical AssociationThe British Astronomical Association was founded in 1890 and now has about 3,000 members. Its leading features are:

Membership –Open to all persons interested in astronomy.

Objectives –(1) The organisation of observers, including those using small telescopes or binoculars, for mutual help. (2) The analysis and publication of observations.(3) The circulation of current astronomical information.(4) The encouragement of a popular interest in astronomy.

Methods –(1) The organisation of members in sections under experienced directors.(2) The publication of a Journal, Newsletters, a Handbook, Circulars and Bulletins.(3) The holding of meetings.(4) The maintenance of a collection of astronomical instruments for loan to members.(5) The affiliation of schools and societies.

Annual Subscriptions These are due August 1 each year. Current rates are available from the Office.

MEETINGS

Meetings are held at approximately monthly intervals, excluding July and August. Many are in London on either Wednesdays (starting at 17.30) or Saturdays (starting at 14.30). Meetings are also held at venues around the country. A very popular weekend meeting is held near Winchester in the spring and an Exhibition is normally held evey two years in June. Back–to–Basics meetings for beginners are held outside London each year, usually in March and October. Observers’ workshops are also held twice per year. Many observing sections hold meetings every few years, some annually. Full details of the current programme are available from the office and the website.

PUBLICATIONS

The principal publications are the Journal and the Handbook. In addition, e–mailed bulletins, paper circulars and section newsletters are available to members.The Journal is published six times a year. It contains reports of meetings, reports of the sections, papers, reviews, letters, images and notes on current astronomical news. The complete set of Journals from 1890 is available on DVD.Occasional longer Memoirs containing detailed section reports. This Handbook, prepared by the Computing Section, is published annually.The e–bulletins/Circulars give early information on new and predicted events such as planetary phenomena and the discovery of novae and comets. The complete set of Circulars is available on CD.

REGISTERED OFFICE

The Registered Office of the Association is at Burlington House, Piccadilly, London, W1J 0DU.Email: [email protected] 020 7734 4145. Hours are 09.00 to 17.00, Monday to Friday.

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Printed by Berforts Ltd. +44 (0)1424 722733

The BAA on the InternetBAA Home Page

http://britastro.org

This website contains information about theBAA and how to become a member; it gives details

about the meetings, publications and merchandise for sale.There is a “members only” area, plus links to pages

maintained by the Observing Sections.You can find news items, data on new comets,asteroid occultations and other topical events,

plus photo galleries and links to many other sourcesof astronomical information.

BAA Computing Section

http://britastro.org/computing

This website complements the Handbook by providing extra material for which there is not room in the Handbook.

This includes : charts for many minor planets, calculational forms,

graphical applications such as what is observable at any time and positions of satellites of major planets.

Constant data that do not need to be printed every year in the Handbook together with links to other websites.

BAA Journal

http://britastro.org/journal


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