The CHESTERFIELD ASTRONOMICAL SOCIETY

Newsletter APRIL 2016

CAS website www.chesterfield-as.org.uk Registered Charity No. 514048

Secretary: Marilyn Bentley

Newsletter: Sue Silver newsletter@chesterfield-as.org.uk

President – Reinhold Gasser. Secretary – Marilyn Bentley. Treasurer – Graham Leaver. Newsletter Editor – Sue Silver. Committee Members: – Sue Silver, Peter Cory and Calvin Karpenko

Subscriptions - full membership £60 or £6 per month by Standing Order (10 months) Senior citizens (60 yrs and over) and students (18 yrs and over) £40 or £4 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).

.

CAS News SAD NEWS We have to start this letter off on a sad note. Most of you will know by now that one of our longest serving members, Graham Jenkinson, has passed away. He was a really nice, genuine person. A man of few words but great knowledge. He will be sadly missed. Peter Davison has put a few words together about him..........

Graham Jenkinson 1954-2016

It is with great sadness that the Society has to announce the death of one of its longest serving members. Graham Jenkinson died in the Royal Hallamshire Hospital in Sheffield on Monday 7th March, following an accident he had at home a few days earlier. He was 61 years old. He was an active member of CAS for over 45 years and held the position of Director of Maintenance for a number of years. During this time he would be at the observatory every free moment he had to work on our 18" reflecting telescope and the clubhouse making improvements or repairs. He later became President of the society until ill heath forced him to stand down. Graham was able to turn his hand to almost anything. He was a great mirror maker; he ground mirrors ranging from 6" up to12” in size. He built several telescopes to house the mirrors that he made including a 6” Dobsonian which he donated to the society. His observatory at home housed a 12” reflector that he designed and built. Other telescopes that Graham made included a 12” Dobsonian which had an electric drive to track objects across the night sky. This telescope, as Graham says, was “transportable rather the portable” because of the weight of it. One of his future projects was to make it lighter; unfortunately it was not to be. He also built an 8” reflector which he used as a guide scope. Graham was a keen astro-photographer and many of his pictures have been published in various astronomy magazines over the years. Most of our newsletters have included brilliant photographs taken by Graham. Samples can be found in his gallery on this website.

Graham was friends with many famous astronomers including Sir Patrick Moore and Graham would visit him whenever he was down in the Selsey area and Sir Patrick would reciprocate whenever he was visiting Chesterfield. Graham loved the outdoors and was a keen walker. Over the years he completed many long walks including the Pennine Way and the Limey Way just to name two. He also loved to go camping and enjoyed the astro-camps that the society organised. Graham leaves his wife Maureen and son Tim. Our thoughts are with his family. Graham and Sir Patrick Moore. Graham named this picture “Two Mad Astronomers” Rest in Peace, Graham. Thank you for this. I have used one of Graham's photos for the header page of Comet Lovejoy taken on 26th January 2015 with a 19 minute exposure. He was a great astrophotographer.

Graham sent me this back in June last year. I and several other members thought this was as good as anything we had seen anywhere. It is a great picture of the Owl Nebula "1 25 mins 33 secs total exposure time 50 frames". I could not miss including this one! Coming up................ Talk on the 15th April by Clare Burrage Entitled: The dark side of the universe Billions of years ago the Big Bang sent everything flying apart. In theory, gravity should stop galaxies from moving apart and matter should eventually re-collapse on itself. Surprisingly, we have learnt that galaxies are actually moving apart with ever-increasing speed. Nothing in our current knowledge of physics can explain this, but theorists are developing a solution: dark energy. Roughly 70% of our universe is comprised of dark energy and yet very little is known about it. I will describe what we currently know about the nature of dark energy, how it affects other matter in the universe, and what plans we have for observing this mysterious force. REMINDER!...........THIS WEEKEND! HADDON GROVE ASTRO-CAMP – Friday 1st April to Sunday 3rd April If you want to join the Star Party at Haddon Gove and don't want to stay the night you can just turn up for the evening and enjoy the dark skies. If you need any information please contact Peter Davison either by email peterdavison45@virginmedia.com or by phone 07806670609.

Photo Gallery............ These are taken by Graham Leaver...................

This one taken 11/02/16 Petavious taken 11/02/16

Apennines Autolycus 15/02/16 Cassini Alpine Valley 15/02/16

Hyginus 15/02/16 Langrenus 11/02/16

Mare Crisium 11/02/16 Mare Crisium Cleomedes 11/02/16

More from Graham taken on 5th March..........

These have been taken over about an hour and you can see the tiny dot to the right which is Ganymede. These two from Graham on 17/30/16

Jupiter with moon (left of planet) M101 (which Graham thinks is "underexposed")

These also from Graham Leaver taken 25/03/16 of the Sun.

This was taken 28/03/16 Thanks for these Graham. This is from Mark Eustace taken 25/03/16

These two are from Peter Davison..............30/03/16

Thanks Peter The two moons on this one are Io and Europa, they have been close together for a few days now. Things to see in April.............. Sunday 3rd Jupiter's largest moon Ganymede emerges from the planet's shadow just after 22:00 BST. You can catch the moon's reappearance slightly less than a planet diameter to the east and slightly south of Jupiter's centre. Wednesday 6th Venus and the waning crescent Moon (2% lit) should be visible just before sunrise low in the east. At 08:37 BST the Moon's illuminated side will start to cover the planet's disc. Venus will remain hidden from view until 08:57 BST. Thursday 7th Today's new Moon is also at perigee – the point in the Moon's lunar orbit when it is closest to Earth. This is what is known as a perigee- syzygy new Moon. The term syzygy describes three celestial bodies being aligned. Friday 8th Mercury sits 6° from the waxing crescent Moon (2% lit) in the evening twilight. Look for the pair low in the west from about twenty minutes after sunset. Saturday 9th The magnificent globular cluster M3 reaches its highest point in the sky, due south around 02:00 BST.

Monday 11th The Whirlpool Galaxy, M51, lies almost overhead around 02:00 BST. This means that its light is passing through the thinnest layer of atmosphere possible – in theory giving you the best possible view. Tuesday 12th Jupiter's moon Callisto undergoes an eclipse this morning. The moon will be clearly visible at 00:30 BST on the 11th entering Jupiter's shadow shortly after. It emerges from the shadow at 03:10 BST. Sunday 17th Mars reaches a stationary point at 03:00 BST. Before this time the planet will have been moving eastward against the stars, afterwards, it will be moving west, marking the beginning of another period of retrograde motion for the planet. Monday 18th The waxing gibbous Moon (85% lit) is 3° south of bright Jupiter at 03:00 BST visible low in the west. This dramatic pairing can be seen from as soon as the sky darkens on the 17th when the separation will be slightly larger at 4.25°. Wednesday 20th Jupiter's outer Galilean moon, Callisto, will be transiting the planet's disc from 01:30 – 4:25 BST. The end of this event occurs as the dawn sky is brightening. Thursday 21st The Moon reaches apogee this afternoon – the point where it is farthest from the Earth in its orbit. Full Moon is tomorrow, making this an apogee-syzygy full Moon. Friday 22nd The April Lyrid meteor shower is active between 16th and 25th April with peak activity expected on the 22nd. Unfortunately this year's shower will be badly affected by tonight's full Moon. Usual peak activity gives a zenithal hourly rate of around 10 meteors per hour. Monday 25th There are two close conjunctions of the Moon with planets today. In the early hours the 92% lit Moon is 4° north of Mars at 03:00 BST, look low in the south. Around midnight, the now 87% lit Moon is 3.5° from Saturn. Thursday 28th Try and locate Jupiter in the daytime sky at 18:50 BST. Its moon Callisto can be found 1.75 times the apparent diameter of Jupiter to the east of the planet's centre. Callisto will disappear into Jupiter's shadow shortly after. Its reappearance just after 21:00 BST is a bit easier to see.

ASTROSTUFF Nine 'monster' stars 30 million times brighter than the Sun discovered by British astronomers The discovery of a cluster of “monster” stars by British astronomers could contribute to the study of gravitational waves. British astronomers have used the Hubble Space Telescope to find a group of nine massive stars 30 million times brighter than the Sun. An international team, led by astronomers from Sheffield University said the cluster, 170,000 light years from Earth, is the largest group of very massive stars identified to date. The discovery raises many new questions about the formation of massive stars and also highlights the continuing capabilities of the now ageing Hubble Space Telescope. The cluster – named R136 – is only a few light years across and is in the Tarantula Nebula within the Large Magellanic Cloud – a satellite galaxy of our own Milky Way. The team said the young cluster hosts many extremely massive, hot and luminous stars whose energy is mostly radiated in the ultra violet – which is why the scientists used Hubble to probe the ultraviolet emission of the cluster.

It includes nine monster stars which are more than 100 times the mass of the Sun and dozens of stars exceeding 50 solar masses. None of the stars identified have unseated R126a1, also in the Tarantula Nebula, as the most massive star in the known universe at more than 250 solar masses. Professor Paul Crowther, from Sheffield University’s Department of Physics and Astronomy, showed with his international team in 2010 the existence of four stars within R136, each more than 150 times the mass of the Sun – these properties were so extreme they exceeded the upper-mass limit for stars that was generally accepted at the time. Now, the team’s new research has shown there are five more stars with more than 100 solar masses in R136, raising many new questions about the formation of massive stars as the origin of these huge creations remains unclear. Identifying individual stars in this crowded region of space was only possible because of the Hubble Telescope (NASA/AP). Saida Caballero-Nieves, also from the university, said: “There have been suggestions that these monsters result from the merger of less extreme stars in close binary systems. “From what we know about the frequency of massive mergers, this scenario cannot account for all the really massive stars that we see in R136, so it would appear that such stars can originate from the star formation process.” Professor Crowther, lead author of the study, published in the monthly notices of the Royal Astronomical Society, said: “Once again, our work demonstrates that, despite being in orbit for over 25 years, there are some areas of science for which Hubble is still uniquely capable.” The professor said this could contribute to the study of gravitational waves – the ripples in space time which were predicted by Albert Einstein and became worldwide news last month when another team announced they had been detected.

FUN STUFF I THINK I'M A MOTH A guy walks into a dentist's office and says, "I think I'm a moth." The dentist replies "You shouldn't be here. You should be seeing a psychiatrist..." The guys replies, "I am seeing a psychiatrist." The dentist says, "Well then what are you doing here?" And the guy says, "Your light was on."

That’s all folks.

Sue This newsletter is sent out to all present members without whom the Society could not survive. Also to previous members and people with an interest in astronomy in the hope that they may wish to join/re-join the Society. If you no longer wish to receive this newsletter by e-mail please let us know. Thank you.