The Southern Astronomer by Brian Halls

The Southern Astronomer No.107 – September/October 2017

SOUTHERN ASTRONOMER THE

MONTHLY MAGAZINE OF WORTHING ASTRONOMERS & WORTHING SKYWATCHERS

Contact of the third kind

The Southern Astronomer No.107– September/October 2017

WORTHING ASTRONOMERS No fees, no Committee; just enjoying the night sky together.

ormed in 2008 by a group of regular and practical observers, Worthing Astronomers is a free to join society now with a membership of over 450 persons, who have a common interest in Astronomy and its associated subjects – no internal politics, no fees, no committees, just astronomy!

The Southern Astronomer This Issue Ringing in The Changes Diary and Observing Planets Observing The Sun Deep Sky Objects for the Autumn Sky map September Sky map October

Our aim is simple – to bring astronomy to the public in general and to help and assist our membership in observing the night sky. 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 those of neighbouring astronomical societies.

….........… ………….. ………….. ………….. ………….. …………..

p.3 p.4 p.5 p.6 p.7 p.8

Cover & Comment The one thing about the long bright summer days is that one particular star can be observed for long periods – our Sun.

We try and meet at least once a month (when weather conditions allow) to do some observing but at the moment we do hold, every two months, a Workshop evening when we get a chance to meet up, exchange ideas and tips and help each other to make the most of observing the sky above us. Occasionally a guest speaker will talk about an aspect of practical, hands on astronomical observing.

This especially so in August when astronomers (professional and amateur alike), eclipse chasers and members of the general public witnessed the eclipsed Sun sweeping west to east across the continental USA on August 21. Several of our members found themselves in the US for the event and we hope they enjoyed it. Here in the UK it was dull and grey so there was not even a chance from the Worthing area to see the partial portion prior to sunset. Fortunately Worthing Skywatchers member Jonathan Green saw it from Devon and dutifully captured the images.

These Workshop evenings are usually held on the first Friday of every other month (February, April, June, August, October and, December) at Goring Methodist Church Hall, Bury Drive (off of Aldsworth Avenue), Worthing, BN12 4XB. The small admission charge of £3 helps pay for the room and free refreshments and goes towards supporting our membership. Doors open at 7.00 pm BST with the meeting starting at 7.30.

The cover picture from Linda Croft and Nick Quinn shows third contact – the diamond ring effect that appears as totality ends and was shot from their observing site in Wyoming.

We can be found at: worthingastronomers.org.uk

The Sun has also been worth observing as well during the last two months as several large sunspot groups have traversed the visible solar face two of these groups were visible during the latter part of August. A report on what the Sun has been up-to is on page 5. This issue of The Southern Astronomer is also going to be my last as I stand down as editor (and group co-ordinator) at the October AGM. On the next page is something that all members of Worthing Astronomers should read and ponder over.

There are several astronomical groups in the coastal area of Sussex - several WA members are also members of the Adur Astronomical Society, who meet every first Monday of the month for a lecture regarding an astronomical subject. Details for the AAS can be found at Adur Astronomical Society.

The last few years has been fascinating and I have enjoyed putting the monthly newsletter together however, as you will notice, this issue, like the one previous covers two months.

CONTRIBUTIONS AND UNSUBSCRIBING Contributions – written articles (word processed in .txt, .doc or .odt format), photographs, letters, advertising copy to the editor should be sent to the editor at the contact address: editor@worthingastronomers.org.uk

Clear Skies.

Contact addresses: Acting joint coordinators - info@worthingastronomers.org.uk – general society details, Janet Halls or Brian Halls (not after October)

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 inbox.

treasurer@worthingastronomers.org.uk – donations contact Janet Halls acting-treasurer.

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.

outreach@worthingastronomers.org.uk – events contact Steve Bassett, Mike Williams

If you like the newsletter or its content please feel free to distribute it to anyone you know who might be interested. Content is subject to copyright to the group and/or the individuals whose images or articles are used.

website@worthingastronomers.org.uk – contact for website Perry Wilkins editor@worthingastronomers.org.uk – newsletter content detail Brian Halls (not after October)

The Southern Astronomer No.107– September/October 2017

RINGING IN THE CHANGES

We also need an editor for this newsletter. Some ideas have already been put forward about the future of the newsletter but that is down to the new Working Group to work on and inform the membership.

These childish antics by people (always it seems, Men!!) still go on but I am pleased to say have never raised their ugly heads in Worthing Astronomers. We are quite a lackadaisical lot, and internal club politics do not exist (at least I hope they don’t!) However we are now at a point where there must be a change in the leadership (for the want of a better word) in our group.

These are questions you will need to ponder now before October. If however, there is no person (or persons) willing to take up the primary admin rôle, we as a group may have to think about the future of Worthing Astronomers – perhaps even folding Worthing Astronomers and transferring our funds balance to an organisation with similar principles and ethos to freely carry on the work of promoting astronomy and sharing the night sky with as many others as we can.

Running the newsletter is informative – and might attract someone with a flair for design and words. As above, this could be a joint witch on the TV, radio or open any news service and we seem effort between members. Help and assistance from myself will be to get a continual stream of politics, Brexit, Europe, available over a transition period so no one is to be thrown into the parliament, the US etc. No wonder we escape to the sanity of deep-end. a hobby like astronomy to take our minds off of that sort of thing. We have a magnificent website managed by Perry Wilkins which is, However… like many astronomy groups in the UK (and the world) our ‘shop window’ to those who are interested in joining an astronomy group. A few years ago, the President and Secretary of an astronomy Both the worthingastronomers.org.uk address and email society in a major university city located in southern England (I won’t contacts associated with it are very much integrated into online name them or their group to save the blushes of the innocent) were search engines and various organisations that approach us. I know standing down and set up a new President to be elected at their that Perry has agreed to carry on the website management. AGM. Another committee member was also nominated to stand for President by the general membership. This would have meant a A special thank you to David Woods who has kindly hosted our vote; the membership candidate was very popular and would not website on his servers free of charge for a number of years. stand down his nomination. So the outgoing President and Secretary could do the only thing that that could...they expelled from Our outreach events prove popular with members and public alike their society that candidate so their nominee became President with and these have been managed by Steve Bassett and Mike Williams out a contest and I hope these events will be carried on in their very capable hands. As the Astronomy Republic blog said at the time, it would have a bought a proud twinkle to the eye of old Joe Stalin himself. Two members of the Working Group have had to stand down this year – Chris Pennells and Graham Williams – and I would again like Sadly this was not unique. Other astronomy groups make a point of to take this opportunity to thank them both for their respective inputs cold shouldering or even ’bad-mouthing’ other astronomy groups to into the group. organisations that hand out grants yearly – as if other astronomy groups were going to somehow ‘steal’ the photons meant for their There are of course the bimonthly meetings. This was a feature we own telescopes. had not intended to have on a regular basis – they were to be ‘oneoffs’ but they have proved popular and grown on us. They are also a Bonkers!! And of course light years away from the fun of meeting good financial source for our funds. Is there still a need for them or others to enjoy the hobby of astronomy. do we return to our original aim of only meeting up at the telescope?

In October 2016 it was announced that both Jan and myself were standing down from our roles in the WA at the AGM in 2017. This is for a variety of personal reasons but nine years leading the group is a long time and we have always believed that no person or persons should be ‘at the top’ for too long. We will still remain as ordinary members of the group and give it our support.

Hopefully, it will not come to this, but it is now down to you, the membership, to decide. Brian Halls

After these years at the helm, now is the time for new ideas, and perhaps a new direction for Worthing Astronomers. We will be having our AGM on October 6 where new appointments may be nominated and a discussions for the future made. We have always had a Working Group. Not so much a Committee but a group of individuals who have put some input into the group and have had ideas run past them concerning matters. At the moment we have had a nomination for Treasurer, Richard Pierce, however there is no indication that there is any one else or group of people wishing to carry on with the direct running of the group. This a great shame but hopefully there might be those who will come forward to carry the group into its second decade. We need someone to cover the post of Co-ordinator (basically a Secretary) who is the first point of contact for public and others with the group. The info@worthingastronomers.org.uk email address is the WA’s primary contact address and would be transferred to the new appointee. They are also responsible for the database of members – that is those who have subscribed to membership via the link on the WA website. This needs to be passed on for safe keeping, so keeping in line with the requirements of the Data Protection Act. This job could be a members job share.

The Southern Astronomer No.107– September/October 2017

ASTRONOMY

LUNAR PHASES FOR OCTOBER

In September & October 2017

Day 1 5 6 8 9 12 19

21 06 12 17 19 25 01 26 18 27 22 28 29 01 31

All times expressed as Universal Time (UTC – Co-ordinated Universal Time) unless otherwise stated which can be considered the same as GMT i.e Summer Time, minus 1 hour. Information given, unless otherwise stated is for the 15th of the month at 21.30UT. Lunar and other phenomena in the Quick View Diary are shown to the nearest hour where possible. Meteorological Summer ends at the beginning of September but for us normal people that change over comes at the Equinox; from then on, the evenings start getting progressively darker earlier and earlier – the astronomy season has begun. The clocks revert to GMT at the end of October.

SEPTEMBER QUICK VIEW DIARY Day 1 5 6 12 13 18 20 22 27 28 30

UT Sunrise 06.02 Sunset 17 44 Full Moon Workshop and AGM Mercury superior conjunction Moon at perigee Moon: Last Quarter Uranus at opposition New Moon Moon at apogee Jupiter at conjunction Moon: First Quarter International Observe The Moon Night British Summer Time ends Sunrise 06.52 Sunset 16.42

LUNAR PHASES FOR OCTOBER

UT 05 07 12 06 03 05 20 05 03

Sunrise 05.16 Sunset 18.51 Neptune at opposition Full Moon Mercury greatest elongation west 18° Moon: Last Quarter Moon at perigee New Moon Equinox Moon at apogee Moon: First Quarter Sunrise 06.10 Sunset 17.46

LUNAR PHASES FOR SEPTEMBER

and October returning to our evening skies in early January. Mars is a morning object, rising about an hour and a half before the Sun; it remains a morning object for the remainder of the year before coming to opposition in 2018. Jupiter is at conjunction with the Sun on October 26 and returns as a morning object, rising just before the Sun, for the remainder of 2017. Low in the SSW part of the sky is Saturn. This beautiful planet has given amateurs some glorious views through their telescopes and the scientists manning the Cassini mission new insights into the planet. By October it will be setting not long after the Sun.

OBSERVING PLANETS Mercury reaches its furthest point westerly in its orbit on September 12 and heads for superior conjunction (furthest point in its orbit from the Earth) on October 8. September is the last, best time to see Mercury as a morning star this year. To compensate for this, the best time to see Mercury as an evening star will be in late November when it reaches its greatest easterly point in its orbit on November 24; Mercury is best seen in the evenings until inferior conjunction (when the planet lays between us and the Sun) on December 13.

Only the the remaining two outer (proper) planets of the solar system, Uranus and Neptune are visible in the evening skies. Uranus is at opposition on October 19 while Neptune is at opposition in early September (see Diary Notes above.) The annual International Observe The Moon Night (InOMN) event occurs during the evening of October 28. The Moon that evening will be a day past first quarter. Along the terminator line that will be present that night many lunar features – craters, crater plains, valley’s, and many more. Observing events are in the early planning stages – keep an eye on the website for information.

The bright planet Venus is in the morning sky during September

The Southern Astronomer No.107– September/October 2017

OBSERVING THE SUN

unspot activity put a bit of a late spurt on during July and August with the reappearance of an old group that appears to be maintaining its activity over a long period of time.

Active Region (AR) 2665 (above), had been one of the largest sunspot groups visible for several months, though historically speaking it was a small but very intense group. The size of the group compared with the rest of the solar disk can be seen in the calcium and hydrogen alpha images taken by John Bush (right.) AR 2665 in Calcium light

What was notable was that it was a low latitude southern group (centred approx 7°S). It returned in early August, though it had decayed considerably during its journey across the farside of the Sun in the intervening couple of weeks or so – the Sun takes just under 28 days to rotate on its axis or a rate of just over 13° a day. During mid August another large group (AR 2671)made its appearance (centred about 14°N). This group was a large spread out region of activity reaching, during its time 23° of longitude or (approximately) 160000 kilometres.

AR2671 2017 Aug 20 © Brian Halls/Cokeham Observatory

Rapidly following this, on August 20 another large group (centred at about 7°N) appeared on the limb of the Sun – AR2672 (above.) What was interesting was the large leading spot in that group showed signs of something known as the Wilson Effect – named after a Scottish physician and amateur astronomer of the late 18century who noted that the umbra of some spots appeared as slight depressions in the surface of the photosphere. It has been debated weather some sunspots are physically depressed into the photosphere or was it just an illusion? The answer may lay in the higher transparency of the spot material compared to the photosphere. The pictures, plus a detail are on the next page. What do you think?

...and in h-alpha

Brian State observed the Sun on 31 days in July and 29 in June – the fine weather helping astronomy and not hindering as is usual!

Both images © John Bush

The Southern Astronomer No.107– September/October 2017 The white light images shown (the monochrome pictures) were taken using a special eyepiece called a ’wedge’ that divides the rays from the Sun into light and energy (heat, radiation etc.) This latter will destroy eyesight, so the wedge passes the nasty stuff onto a heat sink while the light passes through a number of filters to reduce glare and absorb any residual heat and into (in this case) a camera. Unobstructed and clear views of the photosphere are visible and is enhanced by a continuum filter which picks up the surface granulation The two colour pictures by John Bush use special interference filters that pass certain wavelengths of light into the camera. The top picture has an ultra-violet filter operating at the ca-II range of the spectrum that passes the light of calcium into the camera – the human eye is not sensitive to see the detail in that image which is shown which is as well, UV light can harm the human eye. The lower picture passes the red-light of hydrogen alpha into the eyepiece/camera. The area of Sun pictured is the chromosphere – an area that lays above the photosphere. The only time the chromosphere is visible to the unaided eye is at the time of a total solar eclipse - see the picture on the front page of this newsletter and you will see three prominences around the edge of the Sun.

Wilson Effect? Detail from original image Observatory

ONLY LOOK AT THE SUN WITH GREAT CARE. IF IN DOUBT, DON’T!

DEEP SKY OBSERVING OBJECTS FOR THE AUTUMN SUBJECT

TYPE

Constellation

MAG

RA (h m)

DEC (° ' )

NGC7662

Planetary Neb

Andromeda

8.6

23 25.9

+42 32

NGC7686

Open Cluster

Andromeda

5.6

23 30.1

+49 08

NGC7585

Galaxy

Aquarius

11.4

23 18.0

-04 39

NGC7606

Galaxy

Aquarius

10.8

23 19.1

-08 29

NGC7721

Galaxy

Aquarius

11.6

23 38.8

-06 31

NGC7723

Galaxy

Aquarius

11.2

23 39.0

-12 58

NGC7727

Galaxy

Aquarius

10.6

23 39.9

-12 18

NGC7654

Open Cluster

Cassiopeia

6.9

23 24.2

+61 35

NGC7635

Bright Neb

Cassiopeia

23 20.2

+61 11

NGC7788

Open Cluster

Cassiopeia

9.4

23 56.7

+61 24

NGC7789

Open Cluster

Cassiopeia

6.7

23 57.4

+56 43

NGC7790

Open Cluster

Cassiopeia

8.5

23 58.4

+61 13

Mrk50

Open Cluster

Cepheus

8.5

23 15.3

+60 28

NGC7235

Open Cluster

Cepheus

7.7

22 12.6

+57 17

NGC7261

Open Cluster

Cepheus

8.4

22 20.4

+58 05

NGC7380

Open Cluster

Cepheus

7.2

22 47.3

+58 08

NGC7510

Open Cluster

Cepheus

7.9

23 11.5

+60 34

IC1434

Open Cluster

Lacerta

22 10.5

+52 50

NGC7209

Open Cluster

Lacerta

7.7

22 05.1

+46 29

NGC7243

Open Cluster

Lacerta

6.4

22 15.1

+49 54

NGC7245

Open Cluster

Lacerta

9.2

22 15.3

+54 20

NGC7177

Galaxy

Pegasus

11.2

22 00.7

+17 44

NGC7217

Galaxy

Pegasus

10.1

22 07.9

+31 22

NGC7331

Galaxy

Pegasus

9.5

22 37.1

+34 25

NGC7332

Galaxy

Pegasus

11.1

22 37.4

+23 48

NGC7448

Galaxy

Pegasus

11.7

23 00.1

+15 59

NGC7454

Galaxy

Pegasus

11.8

23 01.1

+16 23

NGC7479

Galaxy

Pegasus

10.9

23 04.9

+12 19

NGC7769

Galaxy

Pegasus

23 51.1

+20 09

NGC7541

Galaxy

Pisces

11.7

23 14.7

+04 32

NGC7562

Galaxy

Pisces

11.6

23 16.0

+06 41

The Southern Astronomer No.107– September/October 2017

The sky mid-evening from Sussex at 21.30 UT, September 15

elphinus is one of the fainter constellations along with A dark sky is best to see the Milky Way – though of course the Equuleus and Sagitta that are visible in the summer night sky colours that are captured by our members in their images are lost which lay south of Cygnus. due to the lack of colour perception in the dark.

Delphinus (The Dolphin) has a distinctive shape and the asterism of 'Jobs Coffin' which is formed by the four bright stars that make up the main body of the dolphin. There are a number of DSO's around the constellation - M2, M15, M27, M71, NGC's 6823, 6905, 6934 and 7006.

Despite that there is nothing like wrapping up warm on a clear evening and going outside to a dark and comfy spot in the garden and watching the Milky Way span out across the heavens. It is in this region that many deep sky and stellar wonders can be observed, even with a small telescope on occasion as these celestial objects are our own 'next-door' neighbours in the universe. Too many to name and describe in the short space available, we'll have a brief look at some of the prominent ones – amazing to the new sky-watcher and old-hand, alike.

Two stars, α and β are known as Sualocin and Rotanev repectively. These are the backwards name of Nicolaus Venator – the latinised name of Niccolò Cacciatore who was the director of Palermo Observatory during the early 19th- century. To remind ourselves, the Milky Way is the galaxy in which our star and ourselves live – as do all the other stars we see in the night sky. Less than a hundred years ago, it was believed that the Milky Way and its contents comprised the whole universe.

Overhead (as in the sky chart above) is Cygnus. This constellation lays in the Milky Way and a look through a pair of binoculars or a small wide-field eyepiece telescope will show many faint stars. Of course from our light-polluted skies we get to see only the brighter stars but, the constellation contains many deep sky wonders – The Our Sun is just one of an estimated 200 - 400 billion stars that make Veil Nebula, The North America Nebula; M39 (NGC 7092) is an up the Milky Way Galaxy and there billions of galaxies out there just open cluster 950 light-years from Earth and visible to the unaided like our own. eye from a dark sky site.

The Southern Astronomer No.107– September/October 2017

The sky mid-evening from Sussex at 21.30 UT, October15

he Summer Triangle which was once a sign of warm summer nights to come when it was rising in the June evening sky is now in the western sky after sunset which mid-month is at 17.13UT (6.13 p.m BST) and the evenings are noticeably beginning to draw in, with more chances of deep sky observing. One of the harbingers of winter nights rises early evening.

magnitude fluctuates from 3.48 to 4.47. Another class of stars worth looking for are double stars. Of these, some are true binaries while others are just coincidental line of sight objects, which can be a test for an observer to see while others are really easy and they can be rewarding for their beautiful colouring.

Open cluster M45 (The Pleiades, or Seven Sisters) is rising in the east during the early evening. Part of Taurus The Bull, M45 is easy to find and a good binocular object. How many stars can you see, first with the unaided eye then with binoculars or with a low power eyepiece?

An example of this contrast in colours is γ-Andromeda. The bright primary (γ 1 ) is a golden yellow colour at 2.3 m . The fainter companion – γ 2 – is an indigo-blue at 5.5 m . The separation of the two objects is 10” so should be visible in a small telescope. If you cannot see the differences in colour do not be alarmed. There is nothing wrong with your telescope optics or even your eyes. The Already higher in the sky than M45 is another Messier object, M31 – human eye processes colours differently from one human to another The Great Spiral Galaxy in Andromeda. From a relatively dark sky so what colours did you see them? A magnification of x50 is site with no or very little light pollution the great fuzzy patch of the recommended. galaxy can be seen with the unaided eye and is probably the furthest object the human eye can see as light from this spiral has Another interesting double is η-Cassiopeiae. The primary, η 1 is a taken just a little over 2 million years to get here, so treat those star just a little larger and brighter than our own Sun and is 3.4 m photons of light as they enter your eye with some respect. while η 2 is an orange star of 7.5 m . Again a power of about x50 is recommended. High overhead is the constellation of Cepheus. The King. Try looking for the star δ-Cephei. This is a variable and is the first star Many more objects in the sky – too many to mention – are worth of a class that is used in the professional astronomers tool box – the scanning for. Cepheid Variables. This star is pulsating which causes its fluctuations. The period for this star is about 5.4 days and the Good hunting and many clear skies for the future.