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The CHESTERFIELD ASTRONOMICAL SOCIETY

Newsletter January 2019

CAS website: www.chesterfield-as.org.uk Registered Charity No. 514048 Our Facebook page: Our Facebook Page Newsletter Editor: Sue Silver Newsletter: newsletter@chesterfield-as.org.uk

President – Mark Eustace; Secretary – Beverley Carr; Treasurer – Catherine Wood.

Committee Members: - Sue Silver, David Frost, John Marsh Co-opted members: John Wheeldon and Linda Moore

Subscriptions - full membership £65 or £6.50 per month by Standing Order (10 months) Senior citizens (60 yrs and over) and students (18 yrs and over) £45 or £4.50 per month by Standing Order (10 months) Juniors members - (17 yrs and under) £0. (All juniors must be accompanied by an adult who must be a fully paid up member). Andromeda Galaxy M31 just showing M32 and M110

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CAS News The CAS Christmas Party – 4th January I hope you are all ready to have your knowledge tested and that you have stockpiled the pork pies in readiness??? It is our members’ Christmas Party time with usual opening time of 8pm so hope you have left enough room after your own Christmas feasts and come and join us. Please bring food to share but be prepared to take home what isn’t eaten. We don’t want to throw food away. CAS Calendars There are still some to sell so if anyone wants one please let Dave Frost know. You can contact him at: david.frost@w3z.co.uk. The calendars are £7 each but are sold on a “first come first served” and collect only basis. We have some at the Observatory so please come over and purchase one (or two). All proceeds, as always, go to the Society. Foreign Currency I’m sure most of us will have some “left over” currency (usually the small change) from our holidays which is practically impossible to get rid of or exchange. Our astute treasurer, Catherine, has found a use for this. She has found somewhere, somehow, that this currency can be turned in British currency. If you have some foreign currency and you don’t want it and want to get rid of it you can help the Society by bringing it to the Observatory and putting it in the collection box on the front desk then Catherine will “magically” get it turned into money for us! Thank you and thanks to Catherine for organising this.

Photo Gallery........................... These are from Dave Simpson........ “I haven't ironed out all the problems getting used to my new monochrome camera yet but I've been blown away by the shots taken through the Hydrogen alpha filter. Moving to a monochrome camera might seem a backward step but this camera can see things my old modified Canon 450d couldn't hope to see. By taking images with red, green and blue filters it is possible to build up a colour image in Photoshop of high quality but entails significantly more complicated processing. By using narrowband filters, eg, Hydrogen alpha, Silicon and Oxygen3 it is possible to build up a very detailed image of nebulae scattered along the Milky Way. The three narrowband images can be put into Photoshop in the red, green and blue channels also which results in a false colour image commonly referred to as the Hubble Palette. Image 1 is the Crescent Nebula NGC6888 in Cygnus. According to Wikipedia it was discovered by Herschel in 1792. It is formed by the fast stellar wind from the Wolf Rayet star WR136 (HD192163) colliding with and energizing the slower moving wind ejected by the star when it became a red giant around 250,000 to 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The inward moving shock wave heats the stellar wind to X-ray-emitting temperatures. Image 2 is the 'Gulf of Mexico' area of the North America nebula, NGC7000 again in Cygnus. I'm having trouble getting good S and O3 images at the moment (these filters exclude all light except for a very narrow band exactly where these emission nebulae emit light so they are very dark and not easy to work with. Visually you'd probably struggle to see a first magnitude star through one but with the aid of computer software they are the bees knees when looking at emission nebulae. Crescent Nebula NGC6888 in Cygnus

The 'Gulf of Mexico' area of the North America nebula, NGC7000 again in Cygnus Brilliant Dave! Great detail. On the other hand..........I just can’t resist a rainbow!

This is from Peter Davison............. “On Friday 7th Dec Mars and Neptune was very close together, in fact you could see them both in the eyepiece at the same time. The photo was taken using the Society's 18" reflector at the focal plane (which means the camera was attached to the telescope without an eyepiece) It was a 5 second exposure, which left Mars over exposed but the blue dot in the bottom left corner is the planet Neptune. Neptune is 4 times the size of the Earth, but is 2.7 billion miles away and Mars is half the size of the Earth and is just over 48.5 million miles away, this makes Neptune 55.6 times further away than Mars is from the Earth.” Thanks Peter This is from Dave Frost....... Finally got my mount back after two months being repaired. I was very keen to try it out with my new William Optics GT81 telescope. This is the 'First Light' (i.e. first use of the scope on Monday night). 20 two minute exposures of the Pleiades were stacked in Deep Sky Stacker and finished off in Photoshop. Impressed with the scope it seems pin sharp to the edges. (see below as well)

“Mark has given me a bit of tutoring on how to change the colour balance of the photo to bring out more blue. This is the result.. Looks a lot better, and more as we normally see it.,,” Thanks Dave These of the Moon are mine....... These were using a Celestron CG5 mount with a Canon DSLR 1100d. This fist one was captured during twilight. The Sun was still shining on the Moon. I have darkened it a little for the effect.

This image was a few hours later on in the same evening. The Sun was well out of the picture now with just a dark(ish) sky. Same set up as above. Both done with multiple images, stacked in Registax and finished in PainShop Pro7. These below are from Dave Simpson......... Firstly two views of Comet Wirtanen. Image 1 is taken on the 9th December with the comet passing through Eridanus. Taken using my Canon 450d camera and a 300mm lens with 40 exposures of 29 seconds on my HEQ5 mount, polar aligned but unguided. The sub exposures were stacked using Deep Sky Stacker set to stack the stars. During a 20 minute series of exposures the comet itself will move significantly through the star field so the resulting image will show the comet smeared across the view. At 29 seconds the comet is too overexposed to show a series of 40 individual dots. This image seems to show the comet split into two as there are two trails. To be honest I have no idea what this means as the stars are all normal round shapes. The image is cropped by roughly half.

Image two is taken on the 12th of Dec, this time using my 622mm f4.9 refractor and my zwo mono camera which produces very good black and white images. The scope has more than twice the focal length of the 300mm lens, the zwo camera has a smaller sensor than the 450d which has the effect of zooming in even further and the comet is now nearly at its closest to Earth so the comet head appears bigger and brighter. This is a series of 16 exposures of 15seconds, again polar aligned but unguided. There appears to be a hazy coma but I believe the tail is pointing almost directly away from us so cannot be seen. The third image shows Mars near conjunction with Neptune in Aquarius on the 9th December. Mars is overexposed and Neptune is arrowed. Note that Mars has moved significantly since this image was taken. Stellarium (or any other planetarium) will show that Neptune has moved slightly to the left of the two stars near Neptune in the shot.

The two lines at the bottom both point to Neptune. Good stuff as always Dave!

Things to see in January 2019........ Tuesday 1st Mag. -.4. Venus appears close to a 21% lit waning crescent Moon in the morning sky. You can see this from around 05:00 UT. Wednesday 2nd This morning gives a solar system line up of Venus, a 13% lit waning crescent Moon, Mag. -1.6 Jupiter and mag. -0.4 Mercury. Venus and the Moon will be first to appear low in the south- southeast at 05:00 UT. Mercury will appear last around 07:30 UT. Thursday 3rd Earth reaches perihelion at 05:19 UT, the point in its orbit when it is closest to the Sun. The distance separating them will be 0.933 AU. This is also when the Sun’s apparent diameter will appear at its largest. Friday 4th The Quadrantid meteor shower peaks at 02:00 UT. Also dust ejected from comet 46P/Wirtanen in 1974 may produce a low-rate shower peaking at 18:26 UT with a radiant just south of the Water Jar asterism in Aquarius. Sunday 6th Our bright morning planet Venus reaches greatest western elongation today, appearing separated from the Sun by 47°. Saturday 12th This evening look out for the 35% waxing crescent Moon positioned 6.3° below mag. +0.6 Mars. Sunday 13th Mag. -0.6 Mercury and mag. +0.9 Saturn are just 1.8° apart in the morning sky. This will be tricky to see with the bright dawn sky both planets appearing very low in the southeast approximately 20 minutes before sunrise. Wednesday 16th Around 23:00 UT you can see the lunar clair obscure effect known as the Twin Spires of Messier. Sunlight passing over craters Messier and Messier A produces two distinct spikes. Monday 21st A total eclipse of the Moon will occur this morning. The eclipsed Moon will lie 7° west of M44, the Beehive Cluster. This full Moon is the first of three perigean Moons for 2019. This starts at 2:37 finishing at 7:48 UT. The greatest eclipse is between 4:41 and 5:43 UT. Tuesday 22nd Appearing low above the southeast horizon at 05:45 UT mag. -1.7 Jupiter will be 2.5° from mag. -4.2 Venus this morning.

Thursday 31st Mag. -1.7 Jupiter, mag. -4.1 Venus and a crescent Moon sit together in this morning’s sky. The 18% lit waning crescent Moon will be positioned between both planets. All three objects can be seen low in the southeast from around 05:30 UT. Coming up........ Friday 11th January 2019 A talk at the Observatory on Exploring the Distant Universe with Gamma Ray Bursts presented by Nial Tanvir Things to remember......... Amazon..................... Please remember if you are ordering anything from Amazon follow the link on our website – this earns us commission!!! Thank you. Also Please check out our Facebook page by following the link below: Our Facebook Page

ASTROSTUFF Will Saturn's Rings Disappear? The Ring rain that falls into the gas giant is so abundant that the icy bands could disappear in 100-300 million years Many an amateur begins their night — and perhaps even their observing career — with a view of Saturn's magnificent rings. But a new study shows this solar system spectacle might be short-lived. When Cassini's final orbits took it inside the rings' inner edge, its last observations returned some surprising data. While the rings have been known to be precipitating down onto the planet since Voyager 2's pass by the planet in 1981, Cassini data showed that this gravitationally driven "ring rain" had been vastly underestimated. Now, James O'Donaghue (NASA Goddard) and colleagues have conducted a new analysis of ground-based data from 2011, taken at the Keck telescope on Mauna Kea, Hawai'i,

revealing that, in addition to raining down on the equator via gravity, icy ring particles also flow in along magnetic field lines to reshape the chemistry of the planet's outer atmosphere. Combined with Cassini data, the new analysis enables the researchers to estimate the rings' remaining lifetime: less than 100 million years, a mere blink in Saturn's 4 billion-year lifetime. The results appear in Icarus. "None of the other gas giants have rings anywhere near the mass and brightness of that seen at Saturn," says coauthor Tom Stallard (University of Leicester, UK). "It strongly suggests that something significant must have happened in the recent geological history of Saturn’s system, and that going back to the age of the dinosaurs, Saturn’s rings must have been even more impressive." Interestingly, simulations of the dynamics in the Saturnian system, conducted a couple years ago by Matija Ćuk (SETI Institute) and colleagues, suggest that Saturn's mid-size moons are also about 100 million years old. "The idea that not only the rings but also many of Saturn’s moons are new is a daunting one, unsettling even," Stallard says, "but it certainly chimes with the surprisingly young age that our observations suggest for the rings." FUN STUFF Just a few things to think about:- Always remember you are unique. Just like everyone else. I am on a seafood diet. I see food, I eat it. Something to cheer you up after your Christmas feasts: the more you weigh the harder you are to kidnap! Stay safe, eat cake! A successful man is one who makes more money than his wife can spend. A successful woman is one who can find such a man. Don’t tell me the sky is the limit when there are footprints on the Moon. Sometimes I wake up Grumpy, sometimes I let her sleep. Just remember: life is too short, smile while you still have teeth!! That’s all folks.

Sue

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