The Southern Astronomer No.86 – November 2015
SOUTHERN ASTRONOMER THE
MONTHLY MAGAZINE OF WORTHING ASTRONOMERS & WORTHING SKYWATCHERS
Above: Bright Aurora of early October inside Ursa Major & right, the large sunspot group responsible for it during late September
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The Southern Astronomer No.86 – November 2015
Astronomy Meetings The groups listed below begin their meetings at 19.30hrs Worthing Astronomers (WA) meet on the first Friday of the month, every two months (February, April, June, August, October and December) at Goring Methodist Church Hall, Bury Drive (off of Aldsworth Avenue) Worthing, BN12 4XB. Admission £3. Adur AS (AAS) meet at Southwick Christian Community Church, 1-5 Roman Crescent, Southwick BN42 4TY, first Monday of the month. Admission: £5 for guests, £3 for members. WA and AAS venues have off road parking facilities and grounds adjacent for setting up telescopes when conditions allow. More monthly details in the Quick View Diary (right). Worthing Astronomers is a free to join society with a membership of over 400 persons, all united with an interest in Astronomy and its associated subjects. With the aid of this newsletter, website, social media, regular star parties, workshops and public observing events we hope to encourage and share our interests in observing the sky with the public, our colleagues in our own group and with neighbouring societies.
This Issue Diary, listings, Workshop and AGM reports Lunar Eclipse picture part 2 November Observing Notes Constellation of the Month – Cetus Monthly sky chart
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QUICK VIEW ASTRO EVENTS DIARY November All times shown are Universal Time For WA and AAS details, see side bar on left
1 Sunrise 0653h : Sunset 1641h 2 AAS: Comets – A tribute to Dave Spooner 3 Venus 0.7°S of Mars (0h) Moon: Last Quarter (12h) 5 Southern Taurid Meteors 7 Moon at apogee – furthest point from Earth (22h) 11 New Moon (17h) 12 Northern Taurid Meteors 17 Mercury at superior conjunction (15h) 18 Leonid Meteors 19 Moon: First Quarter (06h) 20 Neptune 2.7°S of Moon (0h) 23 Moon at perigee – nearest point to Earth (19h) 25 Full Moon – Hunters Moon in the traditional English lunar calendar (22h) 30 Saturn at conjunction (0h) 31 Sunrise 0741h : Sunset 1603h
CONTRIBUTIONS AND UNSUBSCRIBE Contributions – written articles (preferably word processed in .txt, .doc or .odt format), photographs or letters to the editor for the December issue should be in by November 15 and sent to the editor at the contact address: editor@worthingastronomers.org.uk If you no longer wish to subscribe to the group and cancel newsletters and other information, please send an email to: info@worthingastronomers.org.uk with 'Unsubscribe' in the subject line; we do not want our stuff to end up like spam littering your in-box. Volunteers are always welcome: if you want to find out more, call 01903 521205 or drop us a line at the e-mail address above.
Lunar Phases – November 2015
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Cover Page: Worthing Skywatchers member Nigel Bradbury caught the Aurora during early October from Minninglow, Derbyshire. Brian Halls' picture of sunspot active region 2422 shows the group responsible for it as it appeared in late September The planets, November 2015
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The Southern Astronomer No.86 – November 2015
AN INTRODUCTION TO DEEP SKY IMAGING October Workshop Report
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Steve Bassett
ur speaker at the October Workshop was Steve Richards whose work may be familiar to many through the pages of the Sky At Night monthly magazine who spoke on the theme of his well regarded book "Making Every Photon Count.” Steve is also quite local, he is based just north of Steyning and suffers the nice dark skies there that many of us could only wish for. Steve started by talking about the different types of equipment that can be used for astrophotography focusing on the different types of mounts and their suitability and explaining the steps that he then goes through to produce his images using "the Six F's". Find, Focus, Frame, Follow, Film and Finish. Steve mentioned his equipment – he uses an astronomical CCD camera as well as a digital single lens reflex camera (DSLR) to capture images, so his talk is based upon his years of trial and error and experience gained from these differing pieces of equipment. The differences between a dedicated astronomical CCD and a DSLR are few but important. The cost of a good DSLR maybe in the region of about £600 while a CCD camera maybe about £2000. A DSLR will have an infra-red (IR) filter which allows the user to take daytime photographs but which can cause colour problems when taking views of deep-sky objects. Quite often the DSLR can be modified by having this filter removed, but makes it almost useless for ordinary photography unless a removable IR filter is fitted. Modification and removable IR filter can add to the cost. The CCD being a dedicated camera does not have this problem.
NGC 7000 in Cygnus – The North American nebula
Another difference is in the light collecting micro-chips. A DSLR camera will produce 'noise' – discoloured pixels - that might be mistaken for stars in a photograph. This noise is caused by the heat produced by the camera battery as well as ambient conditions. The CCD has a built in cooling system to stop this from happening.
A final image (left) has the light pollution processed out
Steve Richards runs the Chactonbury Observatory at his home near Wiston, West Sussex. He has been actively involved in astrophotography since 2004. For more information and Steve, his images and information about his book please visit his website http://www.nightskyimages.co.uk/ All images in this report by Steve Richards A DSLR camera shoots in colour while a CCD will produce only black and white images so, a set of special colour filters is required to process the images into colour.
AGM BUSINESS REPORT Just prior to the October Workshop talk the group held its annual AGM. Janet Halls gave the Accounts (details, see last issue) and these were proposed by Mike Williams and seconded by Della Griffiths.
Taking all the above into consideration however the DSLR is a useful tool for deep-sky images.
Though a number of enquiries had been made no one had formally put their names forward for any of the positions – so Jan Halls remains Treasurer, Brian Halls remains Co-ordinator. Perry Wilkins is working on revamping the website – though a work in progress one innovation proposed will be a members forum – useful for those members who are not on Facebook. We look forward to see how it all works out. A newsletter editor is still required.
Concentrating on the Six-F's Steve went on to explain how each of the steps can be achieved in more detail taking us through the process as he went. Steve also shared some of his early images with us and some of the staggeringly beautiful narrow band images that he has produced more recently.
From Brian:
Steve also fielded questions from members after the talk. I'm sure that all who attended took some useful information and tips away and I'd like to once again thank Steve for taking the time come along.
The group seems to have levelled out at just over 400 members – this appears to be a stable figure we have had for several months now – new members have joined but others have resigned or their email's seem to have become inoperative and emails bounce back. A sure sign that they have left.
Additional notes, Brian Halls
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The Southern Astronomer No.86 – November 2015
Perigee Moon - Total Lunar Eclipse Images: Part 2
AGM Report
The Facebook group Worthing Skywatchers is very much an entity of its own with a membership of about 400 as well – though there is a membership overlap between the two groups it shows that there are a lot of people who take the enjoyment of looking at the night sky seriously enough to want meet up with other like minded people, Well done Steve, Phil and Mike for their work in enthusing others to look-up not just at Skywatchers but in in Astronomers as well.
As promised, here are a selection of some more lunar eclipse images by members of the group. There have been so many so, apologies if yours are not here.
The weather has not been as good to us as perhaps we would have liked but we have had some success with public outreach and the Sompting school event in the spring, plus the impromptu observing nights at the Honeysuckle Lane and Kithurst Hill venues. Though many of us try and observe as regularly as we can, the weather and pressures of work and other responsibilities don't always allow us to put in as much as we would perhaps like, but when we do, we seem to have really good time. The recent total lunar eclipse is a case in point. We had good weather for it and despite the ungodly hour at which it occurred, many members took the opportunity to witness one of natures beauties. A thank you also to Christine Jones and Bob Turner who have given help to various scouting groups in the area to help the packs get their Stargazing badges. We have held six workshop evenings in the 2014/15 period – halfway through the year we found that we were outgrowing our original venue at Goring URC and we searched for and found the hall where we presently meet – which gives us more room to stretch out. A variety of topics have been discussed but we have held two Telescope Clinics which have proven to be highly popular -we'll do some more in the future as and when needs demand.
A montage from Robin Durant
Ideas and suggestions will be always welcome for future workshops. Many thanks to those who help behind the scenes at the meetings – Chris Pennells, without whom our tea breaks would be so dull and the volunteers, Christa Sutton, Peter Wells who help with the clearing away. Thanks also to Jan Halls who sits at the door taking the revenue and to Trish Williams and Sophie Garbo who have helped Jan in this task. It seems that everyone plays some part and if there is someone I have failed to acknowledge, I apologise. Your contributions have been very much appreciated. Let us hope the 2015/16 period is as good for us as the last one has been. DECEMBER WORKSHOP The December Workshop is still a month away but it will be our group social event – hopefully a mince pie or three, and maybe some nibbles. For the membership (and family) of Worthing Astronomers and Worthing Stargazers the entry fee will be waived (though it will still be £3 for non-members). If there is something you would like us to do for that meeting, let us know but we would like to have a selection of images taken by members over the previous few weeks or months to show case what we have all been doing. There will be, as usual a preview of what is going on in the sky for the coming year. After which we will mingle and if the sky is clear, have a look at the night sky. Below: The October Workshop. Picture Peter Wells.
A detailed view of the Moon by Gary Isherwood
James West observing from Chandlers Ford caught the stars surrounding the Moon
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The Southern Astronomer No.86 – November 2015
OBSERVING NOTES November All times are expressed as Universal (UTC – Co-ordinated Universal Time) and can be considered the same as GMT . Information below, and all sky-map on page 8, is for the 15th of the month unless stated. Darker mornings and evenings give us an extra show during this month – moon and planets aligned in the eastern sky prior to sunrise, several meteor showers plus some interesting deep sky objects – all we need is the clear skies.
W
hen it comes to solar astronomy, the reports in the Southern Astronomer are more of the 'what has been' variety rather than what is going to happen as sunspot behaviour is finicky at the best of times let alone when our nearby star, the Sun, throws a strop and stops behaving as it should, just as it is at the moment.
For amateur astronomers such as ourselves we can make a contribution to these studies about an object that we know so much, while at the same time there are many observational mysteries about which we need to learn more. More information is available on request from the editor. Full Moon (or using the English tradition of full moon names, Hunters Moon) occurs on the 25th. The Moon progressively rises early in the evenings and as such observations of post-full moon features can be made.
Sunspot activity has been very much at a low ebb this last few months though the Sun has been known to throw up a surprise – the bright aurora display seen over much of the Midlands and northern Britain during early October is a case in point when a large coronal hole in the solar atmosphere allowed a number of coronal mass ejections (CME) caused by sunspot magnetic fields 're-connecting' (think of it as a kind of electrical short circuit on a grand scale) to escape into the planetary environment.
The brighter planets cluster in the morning sky before sunrise. As mentioned previously, the waning Moon joins them on the 6th (Jupiter) and the 7th for Mars and Venus. Venus is now past dichotomy (half phase) and is heading out on its orbit away from Earth so its angular diameter is slowly shrinking and its phase increasing.
Skywatchers member, Nigel Bradbury's picture on the front page of this issue shows how it appeared in the skies of northern Britain. The sunspot group pictured with it shows the sunspot group responsible for the CME as it appeared few days previous. This group had grown from a simple sunspot a week or so early into a large and magnetically active region by the time it slipped over the western limb (edge) of the Sun.
Both Mike Williams and Brian Halls saw Venus in the daylight sky during October – it can be usually found if the sky is not too hazy – just a case of knowing where to look as long as it is not too close to the Sun!! An accurately aligned go-to driven telescope or polar aligned equatorial mounted 'scope will find the planet in daylight.
Well done to Brian States who observed the Sun on all 30 days of September. Taking a mean of his daily sunspot number and my own (I observed on only seven days) we get an WA average sunspot number 69.13 (this compares with 63.3 AAVSO; 60.1 BAA and 78.1 SILSO.) The Moon once again is becoming prominent in the sky with the darker mornings at the beginning of the month. On the 7th it will be close to Venus and Mars – a photo opportunity if ever there was one – Jupiter will be a little further to the west. New Moon is on the 11th. For few days after that the young moon may be difficult to make out but as the crescent increases it is worth looking at the Earthshine that illuminates the unlit portion of the Moon. The ruddy colour is caused by sunlight reflecting off of the Earth and bathing the night portion of the Moon in 'earth-shine' – hence the name. One might be forgiven for thinking that not a lot can be observed on the Moon at this time, however observations of lunar features under Earthshine conditions may be useful to the lunar section of the British Astronomical Association (BAA) as observers in the past have reported unusual albedo (lighting) features on the night portion of the Moon. A job for the lunar enthusiast is to see if these observations of unusual features can be replicated under near as possible conditions to the original report.
The diagram above shows the path of an inner planet (Mercury or Venus) and shows the varying phases according to its position in its orbit. Venus will be at 60% - roughly somewhere between the half-phase on the right and the gibbous phase next to it. On the subject of polar alignment November 1st sees the second Polaris Hour of the year. At 0hUT on the 1st, Polaris and the actual northern celestial pole (NCP) are aligned with each other; Polaris lays exactly below the NCP. Assuming that the equatorial telescope is accurately positioned on your local meridian, it is possible to align the polar axis of the telescope to the NCP – also assuming that your telescope has some form of polar alignment mechanism or telescope. This is useful (as we saw at the October Workshop) when we need to take exposures of DSO's either through the telescope directly or, if we piggy back a camera onto the telescope tube. The other Polaris Hour is at midnight on May 1st when Polaris lays exactly above the NCP. Meteor & Comets There are no bright comets visible in November though next month the early morning planets are expected to be joined by a moderately bright comet C/2013 US10 (Catalina) – more about this in the December issue of The Southern Astronomer.
Anything unusually bright near Plato on the 14th?
For example, November 14, is there anything bright in Earthshine near to the crater Plato or does the crater Aristarchus appear coloured in the Earthshine in the early evening of the 17th?
There is quite a bit of activity on the Meteor astronomy front however this month. The annual Taurid Shower peaks at just around new moon on November 12 (see chart, next page).
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The Southern Astronomer No.86 – November 2015 Actually two closely related showers, the Southern portion peaks during the morning of November 5 while the Northern portion peaks after midnight on the 12th. Both streams are associated with short periodic comet Encke. A signature of the combined showers are slow moving meteors. The BAA consider this shower to be a favourable one, though moonlight from the 23 day old Moon may interfere a little for the peak of the Southern Taurids. Expected rates are 10 an hour (ZHR). The Taurids are active between October 20 and November 30 – so if you miss the maximums you still have an opportunity between these dates The second major meteor shower this month is the Leonids which peak at about 07h UT on the morning of November 18 though of course early morning observers may see a good show. Again, the position and phase of the Moon are considered good – no moonlight. Leonid meteors are much faster than the slower Taurids and are described as having persistent trains. A ZHR of about 10 to 15 Graphics this page by Stellarium might be expected. The diagram below shows the position of the radiant relative to the Sickle asterism of the 'head' of Leo. The radiant rises about 22.30 on the 17th. Like all radiant's it is not fixed at one point but drifts from night to night across the star-field. By the end of the month the radiant has drifted into the main 'body' of the Lion. Both the Taurids and Leonids are regular and well known bright meteor storms – one Leonid storm as described by those who saw it appeared as if the stars themselves were moving and Earth was tumbling at high speed towards them – a bit like the old Windows 'star-field' screensaver. Stellar & Deep Sky There is more of the November night sky to appreciate as dusk occurs during the late afternoon and the stars are coming out by tea-time. One of the lesser known constellations is Cetus, The Sea Monster. It is almost due south in the early evening and is the beast that is bought about to harm Andromeda in the legend of Perseus and Andromeda. On old graphical star charts it looks a ferocious creature but on modern star maps of today it is depicted with an outline of a whale. A little of this goes in part to the work of a H A Rey, an artist who though not an astronomer produced a book over sixties years ago called, A New Way of Looking At the Stars. Rey's 'sea-monster' looks nothing like the ugly beast (or indeed the ugly outline) of old star maps. His 'sea-monster' has all the scariness of Wally The Whale but these star map depictions of his are a great way to get youngsters interested in looking at the stars. Though Rey's outlines have never been 'officially' adopted by the International Astronomical Union, some of them do appear on star-maps and look very much like the character they are supposed to depict. Kstars uses a whale like outline and this is depicted on the star map on the next page.
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The Southern Astronomer No.86 – November 2015
One of the most interesting stars in Cetus is oCeti (omicron) or Mira , the first variable star discovered – without the aid of a telescope – in 1593. Mira (The Wonderful) ranges from about 2m to 10m in 332 days and is the first of the Miratype class of variable stars. It is a red giant and a double star; according to the latest Hipparcos measurements, it lies 299 light years from Earth. It reached maximum brightness in the spring of 2015 and is now fading – with a moderate telescope, can you see it? The companion star Mira B, is a fainter white dwarf star (about 5m) and is itself variable; the suspicion is that it is accreating matter from the primary star which causes its variability. The brightest star is Menkar (α-Ceti) which means 'The Nose' – now on modern star maps the brightest star of the tail! It is a red giant and also a wide double star. The companion, 93 Ceti is a blue star at 5.6m. Using star-hopping techniques, from Menkar head about 5°west towards the 3.5m star γ-Ceti (gamma) which a close double star – the primary is yellow while the companion is blue, 3.5m and 6.6m respectively so a small telescope or binoculars may make them out. Now hop about 3°southwest of γ to 4m δ-Ceti (delta). A blue giant star and a Cepheid variable in its own right, it is a marker for one of the few interesting deep sky objects in Cetus, M77 just to the east. This face on spiral galaxy is an object for moderate to large instruments as it is about 9m and is a popular target for deep-sky imaging. Laying between η and ι Ceti (eta and iota) is the planetary nebula, NGC 246 or the Skull Nebula – an appropriate object to seek out near Halloween perhaps; it is better known as the Pac-Man Nebula because of the layout of stars. The nebula is 8m while the
central star is about 11m. In the above star map - showing yet a different outline configuration of Cetus we see that on November 15, three minor planets are also present in the constellation.
interest is that τ has a number of planets orbiting it. It is slightly smaller than our own Sun so any possibly habitable planets will exist in orbits closer to their own star than we are to our own.
In fact, one such planet is believed to exist at an orbit within the so-called Goldilocks Zone (neither too hot Vesta at 6.9m was discovered in 1807 and was the or too cold). Any astronomers who may exist on this fourth minor planet to be found while 471 Papagena planet and who look up into their night sky will see was discovered in 1901, while 39 Laetitia was found our own Sun as a 3m star in the constellation of which in 1859. Vesta lies just about 2° west of ι-Ceti. we call Böotes – perhaps they too may wonder. A star which at first glance looks uninteresting is τCeti (tau) at 3.5m. At 12 light years away it is a star with similar characteristics to the Sun. What is of
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As the chart on the next page shows, there are plenty of objects in the deep sky that can capture our attention this coming month.
The Southern Astronomer No.86 – November 2015 As mentioned earlier, in legend Cetus represents the sea creature bought about by Poseidon the Greek god of the oceans, to destroy princess Andromeda. The artwork on the left is by Sydney Hall from one of the many constellation cards called, The Mirror of Urania (published 1825) that depicted the constellations in an earlier style. As can be seen Menkar (The Nose) is indeed at the nose of the creature. Of interest are some other constellations, that may not be so familiar. To the left is Psalterium Georgii (Georges Harp), while under Cetus' front paws is the constellation of Fornax Chemica (The Chemical Furnace), Macena Electrica (The Electric Generator). Officina Sculptoris (The Sculptor) is the only one of these constellation that still remains. BELOW: The Night Sky from Worthing at or around 21.30UT mid-month
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