ANNOUNCEMENTS 1. HOMEWORK #3 WILL BE HANDED OUT THURSDAY; DUE FOLLOWING THURSDAY. HW #@ due this Thursday at class. HW CLUB THIS WEEK AS USUAL 2. OBSERVING SESSIONS: THIS THURS NIGHT AT SBO AT 8pm 3. SUNDIAL HELP SESSION Tomorrow after HW Club (1pm and 3pm) with Kate Vann 4. BOOKS AND SKY GAZER PROGRAM DISKS NEEDED FOR OBSERVING PROJECTS NOW ON RESERVE ACROSS THE HALL IN THE GEOLOGY LIBRARY. 4. Note taker position filled… THANKS to all that responded. Ms Sheevam and Mr Russum please see me after class. UP FOR DISCUSSION TODAY: THE “MERIDIAN SLICE”, SOLAR CALENDARS & SOLSTICE MARKERS.
Transcript
ANNOUNCEMENTS1. HOMEWORK #3 WILL BE HANDED OUT THURSDAY; DUE FOLLOWING
THURSDAY. HW #@ due this Thursday at class. HW CLUB THIS WEEK
AS USUAL
2. OBSERVING SESSIONS: THIS THURS NIGHT AT SBO AT 8pm
3. SUNDIAL HELP SESSION Tomorrow after HW Club (1pm and 3pm) with
Kate Vann
4. BOOKS AND SKY GAZER PROGRAM DISKS NEEDED FOR
OBSERVING PROJECTS NOW ON RESERVE ACROSS THE HALL IN THE
GEOLOGY LIBRARY.
4. Note taker position filled… THANKS to all that responded. Ms Sheevam
and Mr Russum please see me after class.
UP FOR DISCUSSION TODAY: THE “MERIDIAN SLICE”, SOLAR
CALENDARS & SOLSTICE MARKERS.
AT MID-LATITUDES:
calendars set by
SUN ON HORIZON OR
SUN ON MERIDIAN
*** angle Sun takes across
sky = latitude
CHANGES LOCATION
SIGNIFICANTLY TH
AT LOW LATITUDES
(i.e., in the TROPICS)
THE SUN’S HORIZON
LOCATION CHANGES
LESS AND ALTITUDE
ALONG MERIDIAN
CHANGES VERY LITTLE
WINTER SOLSTICE SUN MOVES ACROSS THE
SKY IN SOUTHERN GREECE
ANGLE SUN LEAVES HORIZON = 90O – LATITUDE
MORE HORIZONTAL AT HIGHER LATITUDES HORIZON
MARKERS MORE EFFECTIVE because SOLSTICE
MARKERS ARE SPREAD FARTHER APART
EAST-WEST IS THE DIMENSION OF TIME IN THE SKY
INTRODUCING THE “MERIDIAN SLICE”:
A SLICE THROUGH THE CELESTIAL SPHERE
ALONG THE MERIDIAN
LOCATION OF THE SUN AT SOLAR NOON,
ALTHOUGH ITS POSITION ALONG THIS SLICE
OF THE SPHERE CHANGES DURING THE
SEASONS…. WHICH IS THE CAUSE OF THE
SEASONS
COMMENTS ON “A PRIVATE UNIVERSE”
DOES THE SUN EVER GO THROUGH THE ZENITH HERE IN BOULDER?
THE “SOLAR ZONE”…the
range of altitudes which the Sun exhibits along the meridian during the year.
23 ½ -23 ½
CHINESE SKY MEASURING
SCALE: “a meridian line”
LOCATES POSITION OF
SUN ALONG THE
MERIDIAN AT SOLAR
NOON.
LOCATION ALONG THE
SCALE SETS THE
SEASONAL CALENDAR
ARROW
INDICATED
THE “SOLAR
ZONE”…ANGLES
IN THE SKY WHERE
SUN IS SEENLATITUDE = 34.5O N
HENAN PROVINCE, CHINA
34.5
90 – 34.5 = 55.5
34.5
CENTER OF THE SOLAR ZONE IS ALWAYS AT THE
CELESTIAL EQUATOR…EVERYWHERE ON EARTH.
THE “MERIDIAN SLICE”
Has the Celestial
Latitude = terrestrial
latitude @ the zenith
Basis of celestial
navigation to
determine one’s
LATITUDE. Measure
the altitude of the
meridian passage of
fixed stars; i.e., fixed
celestial latitudes
*** WHERE ARE THE “SOLAR ZONES” FOR KEY WEST & THE EQUATOR ?
THE “MERIDIAN SLICE”
Has the Celestial
Latitude = terrestrial
latitude @ the zenith
Basis of celestial
navigation to
determine one’s
LATITUDE. Measure
the altitude of the
meridian passage of
fixed stars; i.e., fixed
celestial latitudes
IN THE “TROPICS” AT LATITUDES < |23 ½ DEGREES|, THE SUN GOES THROUGH THE ZENITH TWICE PER YEAR.
THE “MERIDIAN SLICE”
Has the Celestial
Latitude = terrestrial
latitude @ the zenith
Basis of celestial
navigation to
determine one’s
LATITUDE. Measure
the altitude of the
meridian passage of
fixed stars; i.e., fixed
celestial latitudes
IN THE “TROPICS” AT LATITUDES < |23 ½ DEGREES|, THE SUN GOES THROUGH THE ZENITH TWICE PER YEAR.
THE SOLAR ZONE:
AT ANY ONE LOCATION
THIS IS THE FULL RANGE
OF LOCATIONS ALONG
THE MERIDIAN WHERE
THE SUN CAN BE SEEN
DURING THE YEAR. IN
EITHER HEMISPHERE
THE SOLAR ZONE
LOCATES THE SUMMER
(HIGHEST ALTITUDE EDGE
OF SOLAR ZONE) AND
WINTER SOLSTICES. THE
EQUINOX POSITIONS ARE
HALFWAY BETWEEN
THESE TWO EXTREMES.
Summer
solstice on
December 21st
Winter solstice
on December
21st
Summer or
winter makes
little
difference
CHINESE SKY MEASURING
SCALE: “a meridian line”
LOCATES POSITION OF
SUN ALONG THE
MERIDIAN AT SOLAR
NOON.
LOCATION ALONG THE
SCALE SETS THE
SEASONAL CALENDAR
ARROW
INDICATED
THE “SOLAR
ZONE”…ANGLES
IN THE SKY WHERE
SUN IS SEENLATITUDE = 34.5O N
A PARTIAL SOLAR ECLIPSE
AS OBSERVED CROSSING THE
MERIDIAN LINE AT SANTA
MARIA DEGLI ANGELI (near the
train station, Roma Termini, in
downtown Rome, Italy).
The numbers to the right of the
Meridian Line tell us that the
eclipse happened on the 79th
day of the year; i.e., the
meridian line is a calendar.
Altitude of the Sun
“calibrated” only along the
meridian, when it is at its
highest point each day.
Meridian line effect only
seen for ~ 30 minutes
around Solar Noon
18
The Tower of the Winds 1576
19
Tower of the Winds South Wall
Gregorian Calendar Reform (1582)
20
POPE GREGORY USED THE “TOWER OF THE WINDS” IN THE VATICAN TO GREET EUROPEAN HEADS OF STATE …
And THE MERIDIAN LINE HELPED HIM CONVINCE THESE HEADS TO CONVERT THEIR COUNTRY TO THE NEW CALENDAR.
BABYLONIAN/GREEK
SOLUTION WAS TO KEEP
BOTH SUN AND MOON
CYCLES AND INTER-
CALATE BY ADDING AN
ENTIRE 13TH MONTH ON A
2—3 YEAR SCHEDULE
OVER 19 YEARS (“YEAR of
METON”)).
EGYPTIAN SOLUTION
WAS TO ABANDON
LUNAR CYCLE
ALTOGETHER SO THAT
THE YEAR WAS ALWAYS
THE SAME NUMBER OF
DAYS (365) AND MONTHS
(12), but the MONTHS
HAD > 29 DAYS.
THE SOLAR CALENDAR:
“BUSINESS TIME”
THE PROBLEM: CALENDAR MAKERS
WANTED TO INCOPRORATE THE
CYCLES OF BOTH THE SUN AND THE
MOON but…
12 X 29.5 DAYS IN THE LUNAR
MONTH = 354 DAYS 11 ¼ DAYS
SHORT.
THE SOLUTION IS CALLED
“INTERCALATION”… to add or subtract
days or months to keep on the schedule
of the Sun and Moon or on the schedule
of just one of these.
WHEN ROME BECAME
THE POLITICAL AND
MILITARY POWER IN
EUROPE THE LUNAR
CYCLE WAS
ABANDONED IN FAVOR
OF THE EGYPTIAN
SOLAR CALENDAR.
JULIAN CALENDAR started
in March. Thus, e.g., October is
8th month (not 10th as currently)
and February was the last month
of the year. Originally months
alternated 30 and 31 days but
Julius & Augustus “stole” days
from Feb. for their months,.
THE JULIAN CALENDAR
THE EGYPTIAN SOLUTION (c.
300 BCE) WAS TO ABANDON
THE LUNAR CYCLE AND
CREATE A PURE SOLAR
CALENDAR OF 12 X 30 DAY
MONTHS + 5 “FEAST DAYS”.
ADOPTED BY ROME IN 45 BCE
AFTER THE “YEAR OF
CONFUSION” (46 BCE WHICH HAD
465 DAYS TO CORRECT FOR PAST
MISTAKES).
LEAP YEARS WERE ADDED AT THAT
TIME. EVERY YEAR WHOSE
NUMBER IS EVENLY DIVISIBLE BY 4
HAS 366 DAYS….EXTRA DAY ADDED
TO February, the last month of the year
BY 1600s THE CLERGY
NOTICED THAT EASTER
WAS SLOWLY BECOMING
A WARM-WEATHER
SUMMERTIME FESTIVAL,
NOT THE SPRING
REBIRTH SYMBOLICALLY
REQUIRED…POPE
GREGORY WAS
CONVINCED TO CHANGE
THE CALENDAR AND HE
GOT CATHOLIC
COUNTRIES TO CHANGE
BUT NOT THE
PROTESTANT
ONES…e.g., BRITAIN DID
NOT CHANGE UNTIL
1700s.; Russia in 1900s.
GREGORIAN CALENDAR(c. 1600 TO PRESENT)
THE YEAR IS ACTUALLY ~ 11
MINUTES SHY OF 365 ¼ DAYS
LONG.
OVER NEARLY 1600 YEARS THIS
DISCREPANCY CAUSED THE JULIAN
CALENDAR TO BE OFF BY 10 DAYS.
EASTER WAS HAPPENING IN
WARMER AND WARMER WEATHER
POPE GREGORY COMMISIONED A
STUDY TO CHANGE THE CALENDAR
SOLUTION OF ALYOSIUS LILIO
ADOPTED…CENTURY YEARS NOT
DIVISIBLE BY 4 ARE NO LONGER
LEAP YEARS.
SOLSTICES: SUN IS AS FAR
NORTH OR AS FAR SOUTH
AS SUN CAN GET:
CELESTIAL LATITUDE =
+ 23½ o AND – 23½ o.
EQUINOXES: SUN IS ON
THE CELESTIAL EQUATOR
(Celestial latitude = 0). DAY &
NIGHT OF EQUAL LENGTH
OF TIME.
LATITUDE =+23½ O IS CALLED
THE “TROPIC OF CANCER” and
LATITUDE =-23½ O IS CALLED
THE “TROPIC OF CAPRICORN…
IN BETWEEN THESE LATITUDES
ARE THE TROPICS.
THE “FOUR CORNERS OF
THE YEAR”: SOLSTICES
AND EQUINOXES
MARCH 20 OR 21st : SPRING
OR VERNAL EQUINOX (“EQUAL
NIGHT TO DAY”)
JUNE 21ST: SUMMER
SOLSTICE OR MIDSUMMER
{solstice means Sun standing
still (on horizon as it sets)}
SEPTEMBER 21st OR 22nd :
FALL EQUINOX
DECEMBER 21st : WINTER
SOLSTICE
CELESTIAL LATITUDE OF SUN THROUGH THE YEAR…
SOLSTICES AND EQUINOXES IN GREEN
CONTINUES
RED MARKS SHOW APPROXIMATE LOCATIONS OF “CROSS-QUARTER” DAYS
NOTE “TWO SUNS” PHENOMENON: SUN STAYS CLOSE TO SAME TWO
LOCATIONS IN SKY OVER MUCH OF YEAR: SUMMER SUN AND WINTER SUN
“Time of changes”
SUMMER SUN
Winter Sun Winter Sun
ANCIENT TRADITION
IS THAT FIRST DAYS
OF SEASONS ARE
THE CROSS
QUARTER DAYS..
e.g., BELTANE (May
Day) is the FIRST
DAY OF SUMMER.
June 21st, the Summer
Solstice is also called
HIGH OR MID-
SUMMER.
THE CELTIC CROSS-QUARTER
DAYS: THE TRADITIONAL DIVISION
OF THE SEASONS:AUTUMN EQUINOX: SEPT 21—22
(+42 days)
SAMHAIN NOV 1st
(Halloween)
(+50 days)
WINTER SOLSTICE: DEC 21ST
(+43 days)
IMBOLG OR CANDELMAS FEB 2nd
(GROUNDHOG DAY)
(+46 days)
SPRING EQUINOX MAR 20-21
(+42 days)
BELTANE: MAY 1st
(May Day)
(+50 days)
SUMMER SOLSTICE : JUNE 21st
(+42 days)
LAMMAS (or LUGHNASH): AUG 2nd
CELESTIAL LATITUDE OF THE SUN THROUGH THE
YEAR… SOLSTICES AND EQUINOXES IN GREEN
CONTINUES
CONSTELLATIONS OF THE ZODIAC ARE DISTRIBUTED
ALONG THE ECLIPTIC (PURPLE LINE ABOVE) IN THE SKY
TAURUS GEMINI
ARIES CANCER
PISCES LEO
AQUARIUS VIRGO
CAPRICORN LIBRA
SAGITTARIUS SCORPIO
THE 4 “CORNERS” OF THE YEAR: SOLSTICES
AND EQUINOXES
SOLSTICES: “SUN STANDING STILL”. SUN
RISES AND SETS AT ALMOST EXACTLY THE
SAME LOCATIONS FOR APPROXIMATELY 2
WEEKS AROUND THE SOLSTICES
EQUINOXES: “EQUAL NIGHT TO DAY”. SUN
RISES AND SETS DUE EAST AND WEST AND
SO STAYS UP FOR 12 HOURS AND IS DOWN
FOR 12 HOURS.
SOLSTICE MARKERS ARE A WORLD-WIDE
PHENOMENON THAT STRETCHES WAY
BACK INTO TIME. …. FOR EXAMPLE,
SOLSTICE MARKERS
ARE A WORLD-WIDE
PHENOMENON:
OLDEST KNOWN
SOLSTICE MARKERS IN
THE WORLD: CIRCA
5000 BCE IN SOUTHERN
EGYPT. Site mapped by
CU Professor Emeritus
Kim Malville.
** SHOW VIDEO:
COSMIC AFRICA **
NEWGRANGE IN IRELAND
A 5000+ YEAR OLD
PASSAGE TOMB
ALIGNED TO WINTER
SOLSTICE SUNRISE
ONLY AT THE WINTER
SOLSTICE SUNRISE IS
THE INNERMOST
CHAMBER OF THIS
PASSAGE TOMB
ILLUMINATED BY THE
SUN…. An obvious symbol
of rebirth, of the year and so
of humans.
STONEHENGE: EARLIEST ASTRONOMICAL CONSTRUCTION C. 3200 BCE.
WINTER SOLSTICE
SUNSET
KINTRAW WINTER SOLSTICE
MARKER: COUNTY Argyll, Scotland
COLOSSI OF MEMNON
TEMPLE OF
AMENHOTEP III AT
THEBES
ALIGNED WITH
WINTER SOLSTICE
SUNRISE !!
TEMPLE OF
AMENHOTEP III
circa 1350 BCE (1200
YEARS AFTER THE
GREAT PYRAMIDS
AT GIZA
SUN WORSHIP
REPLACED OSIRIS
BITRTH/DEATH/
REBIRTH CULT
SOLAR COURTYARD
ILLUMINATED ONLY
AT WINTER
SOLSTICE DAWN !
SETTING
CALENDARS
BY THE SUN
THE SUNDAGGER
EFFECT ON
MIDSUMMER’S DAY
AT NOON IN CHACO
CANYON, NM… mid-
Winter also marked !!
MACHU PICCHUHIRAM BINGHAM 1913
WINTER SOLSTICE SUNRISE
INTI RYMI: THE LARGEST
SOLSTICE CELEBRATION IN THE
WORLD ! At Cusco in Peru.
QUESTION: WHY WOULD THE WINTER SOLSTICE BE THE ONE WHICH IS MOST
CELEBRATED BY ANCIENT PEOPLES?
1. IT MARKS THE RETURN OF THE LIGHT
2. LESS DAYLIGHT FOR WORKING, MORE TIME FOR
PARTYING.
3. IT’S A SILLY, PAGAN THING.
4. AT THE WINTER SOLSTICE, THE DARKNESS
OVERWHELMS THE LIGHT. IT’S AN EVIL TIME.
5. SOME ANCIENT PEOPLES WERE WORRIED THAT THE
SUN WOULD KEEP GOING SOUTH AND STAY THERE.
QUESTION: WHY WOULD THE WINTER SOLSTICE BE THE ONE WHICH IS MOST
CELEBRATED BY ANCIENT PEOPLES?
1. IT MARKS THE RETURN OF THE LIGHT
2. LESS DAYLIGHT FOR WORKING, MORE TIME FOR
PARTYING
3. IT’S A SILLY, PAGAN THING. IN THE OLD ROMAN
CALENDAR THE WINTER SOLSTICE WAS ON
DECEMBER 25th AND WAS CALLED THE DAY OF THE
UNCONQUERABLE SUN ! CHRISTIANS CO-OPTED IT.
4. AT THE WINTER SOLSTICE, THE DARKNESS
OVERWHELMS THE LIGHT. IT’S AN EVIL TIME.
5. MANY ANCIENT PEOPLES WERE WORRIED THAT THE
Tuesday’s class ended here
WINTER SOLSTICE
SUNSET
HORIZON CALENDAR: requires both a foresight
(typically point on horizon) and backsight (location or
stone marker) … { see Observing Project #2}
HOPI of ARIZONA USE A HORIZON, SUNSET
CALENDAR TO SET THEIR WINTER SOLSTICE
CEREMONY…THE SOYAL.
We’ll take these
one-by-one.
ALL WERE USED
BY ANCIENT
PEOPLE BUT
TRADITION
DIFFERED IN
DIFFERENT
LOCATIONS AND
CULTURES.
METHODS FOR SETTING A
SOLAR CALENDAR
1). RISING OR SETTING POINTS OF THE
SUN ALONG THE HORIZON
{HOPI, EGYPTIAN, CELTS, etc etc}
2) SHADOW OF A GNOMON (VERTICAL
STICK) or PINHOLE IMAGE OF THE SUN
ALONG A MERIDIAN LINE
{EGYPTIAN, CHINESE, EUROPEAN}
3). “ZENITH PASSAGE DAYS” = THE
TWO DAYS PER YEAR THAT THE SUN
GOES EXACTLY THROUGH THE ZENITH
IN THE TROPICS (-23.5O TO + 23.5O)
4). DAY THE SUN FIRST BREAKS THE
HORIZON IN THE FAR NORTH
5). “HELIACAL RISING” OF CERTAIN
KEY STARS (SIRIUS/SOTHIS, PLEIADES)
We’ll take these
one-by-one.
ALL WERE USED
BY ANCIENT
PEOPLE BUT
TRADITION
DIFFERED IN
DIFFERENT
LOCATIONS AND
CULTURES.
METHODS FOR SETTING A
SOLAR CALENDAR
1). RISING OR SETTING POINTS OF THE
SUN ALONG THE HORIZON
{HOPI, EGYPTIAN, CELTS, etc etc}
2) SHADOW OF A GNOMON (VERTICAL
STICK) or PINHOLE IMAGE OF THE SUN
ALONG A MERIDIAN LINE {PUEBLO,
EGYPTIAN, CHINESE, EUROPEAN}
3). “ZENITH PASSAGE DAYS” = THE
TWO DAYS PER YEAR THAT THE SUN
GOES EXACTLY THROUGH THE ZENITH
IN THE TROPICS (-23.5O TO + 23.5O)
4). DAY THE SUN FIRST BREAKS THE
HORIZON IN THE FAR NORTH
5). “HELIACAL RISING” OF CERTAIN
KEY STARS (SIRIUS/SOTHIS, PLEIADES)
NOTES ON INTERCALATING:
JULIAN CALENDAR (45 BCE) had leap years every 4 years…an extra day
added to February (last month of year). BUT that was too much by a tiny bit
*** OVER 16 centuries the 11 minutes discrepancy added up to about 2
weeks that had to be dropped from the calendar to bring it back to
concurrence with the Sun
GREGORIAN CALENDAR (c. 1600 CE) has leap years on century years
only if the century number is evenly divisible by 4
“ATOMIC TIME”: TODAY WE KEEP THE GREGORIAN CALENDAR BUT
ADD OR SUBTRACT “LEAP SECONDS” TO THE ATOMIC CLOCKS TO
KEEP THEM IN STEP WITH THE MOTION OF THE SUN.
BUT IF A CULTURE WANTED TO KEEP “TRUE” TO BOTH THE SEASONS
(i.e., the Sun, Male Energy) AND THE LUNAR PHASES (i.e., the Moon,
Female Energy) THEY NEEDED TO INTERCALATE WITH WHOLE
MONTHS EACH 2 OR 3 YEARS since the 365 ¼ day Solar Year is not an
even number of lunar phase cycles of 29 ½ days. { 29.5 x 12 = 354 days,
11+ days short !)
ALL WERE USED
BY ANCIENT
PEOPLE BUT
TRADITION
DIFFERED IN
DIFFERENT
LOCATIONS AND
CULTURES.
METHODS FOR SETTING A
SOLAR CALENDAR 1) SHADOW OF A GNOMON (VERTICAL
STICK) or PINHOLE IMAGE OF THE
SUN ALONG A MERIDIAN LINE
{EGYPTIAN, CHINESE, EUROPEAN}
2) RISING OR SETTING POINTS OF THE
SUN ALONG THE HORIZON
{HOPI, EGYPTIAN, CELTS, etc etc}
3). “ZENITH PASSAGE DAYS” = THE
TWO DAYS PER YEAR THAT THE SUN
GOES EXACTLY THROUGH THE ZENITH
IN THE TROPICS (-23.5O TO + 23.5O)
4). DAY THE SUN FIRST BREAKS THE
HORIZON IN THE FAR NORTH
5). “HELIACAL RISING” OF CERTAIN
KEY STARS (SIRIUS/SOTHIS, PLEIADES)
QUESTION: WHERE ON EARTH DOES THE SUN GO
DIRECTLY OVERHEAD ON DECEMBER 21ST ?
A). No where. This is “Midwinter” and the Sun is very low in
the sky everywhere.
B). The equator, latitude = 0o
C). The Tropic of Capricorn, latitude = -23½ o
D). Greenwich, England, the “prime meridian”
E). The Tropic of Cancer, latitude = +23½ o
F). Everywhere.
QUESTION: WHERE ON EARTH DOES THE SUN GO
DIRECTLY OVERHEAD ON DECEMBER 21ST ?
A). No where. This is “Midwinter” and the Sun is very low in
the sky everywhere.
B). The equator, latitude = 0o
C). The Tropic of Capricorn, latitude = -23½ o mid-
summer in the southern hemisphere
D). Greenwich, England, the “prime meridian”
E). The Tropic of Cancer, latitude = +23½ o mid-
winter in the northern hemisphere
F). Everywhere.
THE SOLAR ZONE:
AT ANY ONE LOCATION
THIS IS THE FULL RANGE
OF LOCATIONS ALONG
THE MERIDIAN WHERE
THE SUN CAN BE SEEN
DURING THE YEAR. IN
EITHER HEMISPHERE
THE SOLAR ZONE
LOCATES THE SUMMER
(HIGHEST ALTITUDE EDGE
OF SOLAR ZONE) AND
WINTER SOLSTICES. THE
EQUINOX POSITIONS ARE
HALFWAY BETWEEN
THESE TWO EXTREMES.
Summer
solstice on
December 21st
Winter solstice
on December
21st
Who
cares?
THE YEAR IN THE TROPICS
SEASONAL YEAR NOT AS CRITICAL TO MEASURE ACCURATELY.
LENGTHS OF DAYS AND NIGHTS DO NOT VARY SIGNIFICANTLY
OVER THE YEAR AND THE SUN’S RISING AND SETTING POINTS
DO NOT CHANGE SO MUCH DURING THE YEAR AS AT MID-
LATITUDES.
BETWEEN THE TROPICS OF CANCER AND CAPRICORN THE SUN
ATTAINS THE ZENITH AT NOON TWO DAYS PER YEAR. THESE
“ZENITH PASSAGE DAYS” ARE LISTED IN THE NOTES ON PAGE
51.
ZENITH PASSAGE DAYS CAN BE USED TO SET A SEASONAL
CALENDAR ACCURATELY…..BUT ONLY IN THE TROPICS.
IF SOMEONE COULD DETERMINE WHEN THE SUN GOES
EXACTLY THROUGH THE ZENITH.
Eratosthenes of Cyrene
Michael LahanasΕρατοσθένης ο Κυρηναίος :
Μέτρηση μήκους περιφέρειας της γης
WELL OF SYENE IN EGYPT
EXACTLY ON TROPIC OF CANCER
23½ DEGREES NORTH LATITUDE
MAYA TIMES and PLACES
COPAN, HONDURAS…CITY THAT
MADE EARLY MAYA CALENDARS
LATITUDE
=14.5 N
IN THE NEW WORLD THE MAYA
PEOPLE LIVE IN THE TROPICS &
ARE THE GREATEST CALENDAR
MAKERS OF ALL
AT MONTE ALBAN
SUN REFLECTS IN POOL OF
WATER
XOCHICALCO
CENOTES, SACRED
WELLS, ABOUND IN THE
YUCATAN. HERE ARE A
COUPLE AROUND
CHICHEN ITZA
BELOW IS AN
EXAMPLE OF THE
ZENITH SUN
EFFECT (AUG 2013
NATIONAL GEO)
We’ll take these
one-by-one.
ALL WERE USED
BY ANCIENT
PEOPLE BUT
TRADITION
DIFFERED IN
DIFFERENT
LOCATIONS AND
CULTURES.
METHODS FOR SETTING A
SOLAR CALENDAR 1) SHADOW OF A GNOMON (VERTICAL
STICK) or PINHOLE IMAGE OF THE
SUN ALONG A MERIDIAN LINE
{EGYPTIAN, CHINESE, EUROPEAN}
2) RISING OR SETTING POINTS OF THE
SUN ALONG THE HORIZON
{HOPI, EGYPTIAN, CELTS, etc etc}
3). “ZENITH PASSAGE DAYS” = THE
TWO DAYS PER YEAR THAT THE SUN
GOES EXACTLY THROUGH THE ZENITH
IN THE TROPICS (-23.5O TO + 23.5O)
4). DAY THE SUN FIRST BREAKS THE
HORIZON IN THE FAR NORTH
5). “HELIACAL RISING” OF CERTAIN
KEY STARS (SIRIUS/SOTHIS, PLEIADES)
IN THE TROPICS THE SUN CAN GO DIRECTLY OVERHEAD
BUT IN THE ARCTIC AN EVEN NEATER THING CAN HAPPEN
THE MIDNIGHT SUN. MULTIPLE EXPOSURE BELOW IS
TAKEN ABOVE THE ARCTIC CIRCLE (LATITUDE > 90 - 23½)
NATIVES OF NORTHERN CANADA START THEIR YEAR
WHEN SUN FIRST BREAKS THE HORIZON.
ABOVE THE ARCTIC CIRCLE THE SUN CAN STAY ABOVE THE
HORIZON CONTINUOUSLY (24 HOURS PER DAY)
LOWEST POINT OF SUN IN PHOTO IS MIDNIGHT (HIGHEST POINT in opposite direction)
