The Southern Astronomer No.96 – September 2016
SOUTHERN ASTRONOMER THE
MONTHLY MAGAZINE OF WORTHING ASTRONOMERS & WORTHING SKYWATCHERS
The Southern Astronomer No.96 – September 2016
WORTHING ASTRONOMERS No fees, no Committee; just enjoying the night sky together.
F
ormed in 2008 by a group of regular and practical observers, Worthing Astronomers is a free to join society now with a membership of about 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
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. We try and meet at least once a month (when weather conditions allow) to do some observing but 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 or photography.
Astronomy This Month
…............
p.3
Observing Planets
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p.4
Meteors; The Sun; The Moon
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p.5
Workshop Report
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p.6
Perseid & Pizza Report ; AGM Details
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p.7
Monthly Sky Map
………….. p.8
Cover Picture & Comment The Moon being our nearest neighbour in space is always an object that has attracted the artistic eye – both in graphic art work and poetry “...the Moon, in June...” is a simple rhyme.
These Workshop evenings are 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 admission charge of £3 helps pay for the room and free refreshments and goes towards supporting our membership. Doors open at 7.00 pm with the meeting starting at 7.30.
Steve Bassett while looking for the Mercury and Venus conjunction in mid-July captured this shot of his wife, two daughters and their friend atop Cissbury Ring, silhouetted against a blue sky and the rising gibbous Moon. An evocative image I think you will agree. The colour change for the graphics and boxes in the newsletter from summer orange to autumnal brown tells us that the seasons are changing and the bright evenings are going to give way to darker ones.
We can be found at: worthingastronomers.org.uk
For many this is the start of the astronomical observing year with the evening night sky opening up to us once more. Contact addresses: info@worthingastronomers.org.uk – general society details Brian Halls
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 AAS can be found at Adur Astronomical Society
treasurer@worthingastronomers.org.uk – donations contact Janet Halls outreach@worthingastronomers.org.uk – events contact Steve Bassett, Mike Williams
CONTRIBUTIONS AND UNSUBSCRIBING Contributions – written articles (word processed in .txt, .doc or .odt format), photographs, letters, advertising copy to the editor for the October issue should be in by September 15 and sent to the editor at the contact address: editor@worthingastronomers.org.uk
website@worthingastronomers.org.uk – contact for website Perry Wilkins editor@worthingastronomers.org.uk – newsletter content detail Brian Halls
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.
COMING NEXT MONTH
INTERNATIONAL MOON OBSERVING NIGHT
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.
OCTOBER 8
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.
FOR DETAILS SEE THE NEXT NEWSLETTER
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The Southern Astronomer No.96 – September 2016
ASTRONOMY
DEEP SKY OBJECTS
THIS MONTH
SUBJECT TYPE
Constellation
RA (h m)
DEC (° ' )
M2
Glob Cluster
Aquarius
6.5
21 33.5
-00 49
M72
Glob Cluster
Aquarius
9.4
20 53.5
-12 32
All times are expressed as Universal Time (UTC – Co-ordinated Universal Time) and can be considered the same as GMT (i.e. BST minus one hour.)
M73
Open Cluster
Aquarius
8.9
20 59.0
-12 38
NGC7009
Planetary Neb
Aquarius
8.3
21 04.2
-11 22
Both the mornings and evenings are beginning to progressively get darker and with the Autumnal Equinox on September 22 the nights will once again give themselves over for stargazing.
M30
Glob Cluster
Capricornus
7.5
21 40.4
-23 11
NGC6903
Galaxy
Capricornus
11.9
20 23.7
-19 20
NGC6907
Galaxy
Capricornus
11.2
20 25.1
-24 49
IC1396
Cluster + Neb
Cepheus
3.5
21 39.1
+57 30
NGC6939
Open Cluster
Cepheus
7.8
20 31.5
+60 40
NGC4343
Galaxy
Virgo
12.1
12 23.6
+06 57
Basel6
Open Cluster
Cygnus
7.7
20 06.8
+38 21
Cr421
Open Cluster
Cygnus
10.1
20 23.3
+41 42
IC1369
Open Cluster
Cygnus
8.8
21 12.1
+47 44
IC4996
Open Cluster
Cygnus
7.3
20 16.5
+37 38
M29
Open Cluster
Cygnus
6.6
20 23.9
+38 32
M39
Open Cluster
Cygnus
4.6
21 32.2
+48 26
NGC6866
Open Cluster
Cygnus
7.6
20 03.9
+44 10
NGC6871
Open Cluster
Cygnus
5.2
20 05.9
+35 47
NGC6888
Bright Nebula
Cygnus
10
20 12.8
+38 19
NGC6910
Open Cluster
Cygnus
7.4
20 23.2
+40 47
NGC6960
SprNov Rem
Cygnus
7
20 45.7
+30 43
NGC6992
SprNov Rem
Cygnus
7
20 56.4
+31 43
NGC7000
Bright Nebula
Cygnus
4
21 01.8
+44 12
NGC7008
Planetary Neb
Cygnus
12
21 00.5
+54 33
NGC7026
Planetary Neb
Cygnus
12
21 06.3
+47 51
NGC7027
Planetary Neb
Cygnus
9.6
21 07.0
+42 14
NGC7039
Open Cluster
Cygnus
7.6
21 11.2
+45 39
NGC7063
Open Cluster
Cygnus
7
21 24.4
+36 30
NGC7086
Open Cluster
Cygnus
8.4
21 30.5
+51 36
NGC6891
Planetary Neb
Delphinus
10.5
20 15.1
+12 42
NGC6905
Planetary Neb
Delphinus
12
20 22.4
+20 06
NGC6934
Glob Cluster
Delphinus
8.9
20 34.2
+07 24
NGC7006
Glob Cluster
Delphinus
10.6
21 01.5
+16 11
NGC7015
Galaxy
Equuleus
12.5
21 05.6
+11 25
M15
Glob Cluster
Pegasus
6.4
21 30.0
+12 10
NGC6940
Open Cluster
Vulpecula
6.3
20 34.4
+28 17
September 2016
Erratum: Last months issue described the August Full Moon as a ‘Fruit Moon’ – it should have read ‘Grain Moon’ and the Harvest Moon mentioned is actually in October.
QUICK VIEW DIARY 1 2 6 8 9 16 18 21 22 23 26 30
Sunrise 0516h : Sunset 1851h New Moon: Lunation 1159 starts (09h) Neptune at opposition (16h) Moon at apogee (17h) Saturn 3.8°S of Moon (22h) Moon: First Quarter (11h) Full Moon Trad.English ‘Fruit Moon’; Penumbral Lunar Eclipse (19h) Moon at perigee (17h) Aldebaran 0.2°S of Moon (22h) Equinox (14h) Moon: Last Quarter (10h) Jupiter at conjunction (06h) Sunrise 0601h : Sunset 1745h MOON PHASES IN SEPTEMBER
MAG
PARTIAL LUNAR ECLIPSE
A
t the end of September 2015, we had a total lunar eclipse. This year we have a less spectacular partial penumbral lunar eclipse on the 16th – when the Moon passes through the lighter part of the earth’s shadow cast into space. We don’t even get to see it all as the Moon rises from our latitude already in eclipse. It is partial that in as much just a small part of the southern portion of the Moon is not eclipsed. Moon rise for the 16th is 18.14UT and maximum of the eclipse is at 18.54UT. The shadow of the penumbra is just a shade darker than that of the Full Moon and may not be easily discerned but none the less an interesting event. The picture (left) taken by Sophie Garbo shows the 2015 late September Full Moon rising across allotments in Worthing – an apt image for the time of year. © Sophie Garbo
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The Southern Astronomer No.96 – September 2016
The planets mid-month (comparative angular diameters) – timed at 21.30UT
OBSERVING THIS MONTH:
PLANETS M
id month, Mercury lays almost sun-ward from us and is poorly placed for observing, however by the end of the month it will be rising about an hour and three-quarters before the Sun and so given a good eastern sky it may be visible briefly in the pre-dawn sky. Venus is coming round in its orbit a bit more and will look like a slightly gibbous (three-quarter) Moon in even a small to moderate telescope. There is plenty of opportunity to observe the planet in the
Visibility of the planets and Moon, mid-month
evening sky between now and the early new year. As the phase of the planet decreases, it approaches the Earth its angular size in the eyepiece gets larger (diagram, left.) Jupiter is not an easy object to observe as it is fast approaching the Sun and comes to conjunction on September 26. For those with moderate to large telescopes Mars is still worth looking at (or imaging) though it too is low in the western sky after sunset. Saturn with its magnificent rings is still visible to look at. Unfortunately Saturn has been low in the southern skies during this apparition and this situation remains so for another few years but, a good southerly view will not disappoint. Uranus and Neptune are the evening planets at the moment with Neptune coming to opposition on September 2. To most of us they appear as small
The inner planets: evening appearances
star like objects though some amateurs with larger telescopes have been producing some amazing disk images of these two worlds. Give it a try?
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The Southern Astronomer No.96 – September 2016
METEORS & COMETS T here are no major meteor showers visible now until late October however there are a couple of minor meteor outbursts that may be visible.
The first is the Aurigids which actually peak on the last day of August. There is no moon light to hinder the chances of seeing one of these rare meteors. On September 5 another shower starts nearby – the ε-Perseids – which peak on the 9th at about 04h UT. The radiant area is well on-view all night from about 22h–23h local time for mid-norther locations. The diagram, right, shows both radiant’s in early September. As with most meteor ‘shows’ best views are after mid-night but, there are always good chances of evening displays of the shower. There are no bright comets predicted for the autumn and winter months.
T
The Aurigid and epsilon-Perseid radiants early in the month
SUN & MOON OBSERVING
A
he frequency of days without sunspots continues. There were five days in n unusual occurrence takes place on the evening of September 16. The July when no sunspots were officially recorded by the World Data Centre Moon passes through the outer shadow of the Earth that is cast into in Brussels though Brian States recorded 10 spotless days. This is because on space by the light of the Sun. some of these days the sunspots were so small and ill defined they were beyond the grasp of most telescopes. This a partial penumbral eclipse of the Moon (see page 3). Much of the action occurs before moon rise here in the UK but the latter stages of the event do I myself recorded a spotless day on July 4 when I was projecting the Sun but occur while the Moon is above our horizon. when I viewed the Sun through the same ‘scope using a solar-wedge, I made out two extremely small clusters of sunspots – this was a spotty day according to the WDC! In July, sunspots were confined to individual or small groups though two closely spaced groups appeared at the beginning of July and were crossing the centre of the disk mid-month (see the August issue of this newsletter). When this same portion of the Sun rotated into view on August 8, it was again quite active with three defined sunspot areas (or active regions as they are called). These small groups finally disappeared on August 20 – they remained very much static in appearance, with minor changes in spot formations within the groups. From this we know that magnetic activity is still occurring in these areas of the Sun but is ‘quiet’ as the magnetic fields ‘cool’ the surface of the Sun where they break through and appear to darken the solar surface – spots! We shall see how quiet or active these magnetic regions are on or around the first week end of September as these portions of the Sun once more rotate into view. Will they be there or will they have decayed?
The schematic above shows the three major events of the journey of the Moon through the shadow of the Earth; {1} is first contact of the Moon with the shadow at 16.54 UT and {7} last contact by the Moon with Earth’s shadow at 20.54 UT. The central (unnumbered) circle marks mid-eclipse at 18.54UT which is about 40 minutes after moon rise when the Moon will be about 6.5° above the local eastern horizon.
JULY Member Brian States, observing from Guildford, recorded solar observations on 29 days in July which produced a personal daily sunspot average of 26.7 with the spottiest day being recorded as July 11.
What will we see? A lot depends on the state of the transparency of the Earth’s atmosphere, the shadow of which is being thrown into space. It is likely we will witness dimming of the northern part of the face of the Moon while the lunar south pole (Tycho, Clavius area) will be just outside the shadow and will remain bright.
For the first time in several months I to was able to get to observe the Sun on more days than of late – 13 days(!) which produced a personal sunspot number of 25. If we average our two results we get a WA sunspot number of 25.85. If we compare this with the BAA = 25.6 ; AAVSO = 27.1; WDC = 32.5 - we see that our figures are not too far off when compared with amateur (BAA/AAVSO) and professional astronomers using a network of world wide observatories (WDC).
No doubt a great chance for those astro-photographers to capture some contrasting pictures of the Moon but also of course a great chance to see something in the sky going on without any form of telescopic aid. Binoculars or low power eyepieces on telescopes will also produce whole image views of the Moon with which see this unusual type of lunar eclipse.
If you are unable to observe the Sun for any reason why not visit some websites which will show you our nearest star in action: http://web.ct.astro.it/sun/ ; http://sidc.oma.be/
Don’t forget times are in UTC format – add 1hour for Summer Time
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The Southern Astronomer No.96 – September 2016
AUGUST WORKSHOP REPORT:
D
espite it being the start of the summer holidays for many, over 30 members turned up for the August Workshop. The main presentation this month was a different one from the normal, with an historical look at astronomy. Member Bob Turner spoke about one of the most dynamic astronomers of the late nineteenth and twentieth centuries – George Ellery Hale. Bob started with an overview. Hale was born in Chicago, on July 29, 1868. His father made his fortune from building passenger elevators (lifts!) when Chicago was rebuilt after its great fire in 1871. His mother encouraged his love of reading while his father supported his technical inquiring mind. At the age of 13 he built his first astronomical refractor from a cardboard tube and second hand optics. This was replaced with a more powerful 4-inch Hale, circa 1913 telescope in 1882 so Hale could observe the December 6 transit of Venus. developed for future astronomical telescopes. He went on to the Massachusetts Institute of Technology (MIT) and came under the influence of E C Pickering at the Harvard Observatory where the young Hale worked. While he was a student he invented a special spectroscope to observe the Sun – a spectrohelioscope, where solar features not visible to the human eye could be observed. He later studied in Europe and worked with some great names, Janssen, Huggins, Planck to name a few. He returned to the States as an Associate professor in Astronomy and Physics at Chicago University. It was here that he began to look into financing a large telescope for the university. Hale got friendly with the colourful wealthy financier Charles T Yerkes and persuaded him to finance a large 40-inch refracting telescope. Hale and Yerkes fell out over the cost of lenses and the engineering of the telescope itself but all in all, Yerkes stumped up nearly $350 thousand dollars (millions by todays standards) for the telescope and observatory that still bares his name. Andrew Carnigie the multi-millionaire was the next patron who fell under the awe of Hale. He financed what is today known as the Hooker 100-inch telescope on Mount Wilson. Hale was also responsible for the Snow Telescope, also part of the Mount Wilson complex, a massive solar telescope that could produce high quality images of the Sun both in white light but also in varying colours of the spectrum – mainly hydrogen alpha which showed the Sun in ways no one had seen before. It was Hale who discovered that sunspot groups had differing magnetic polarities, proving that sunspots were the results of solar magnetic fields. Certainly the telescope that Hale is best remembered for, and named after him is the Mount Palomar 200-inch reflector. The story of the Hale telescope is as interesting as that of Hale himself and Bob gave an interesting account of the technologies required to build the instrument – from mirror to the tube and mount that were developed just for this project but which were
The 200-inch was conceived as early as 1923 and there were engineering problems surrounding the creating of the 200-inch glass blank that would finally be used as a mirror. Cornings (famous for their Pyrex glass ware) were hired to do the casting and by 1934 the glass was ready to be cast into its mould, but it was to take six years for them to perfect a usable casting.
Whirlpool Galaxy © Steve Goddard
Alex Vincent showed some images of the eclipsing binary star, RS CVn which under goes rapid brightening and fading over a period of several days.
Hand in hand with the glass technology was the mechanics of building a suitable telescope tube and mount that would hold the telescope firmly. A engineering achievement in every way. It is sad to think that Hale never got to see the telescope named after him in action – he died on February 21, 1938 and it was ten years later on January 28, 1948, this magnificent instrument saw ‘first light’. Bob’s talk was greeted with a warm and appreciative applause. During the tea break it was the chance for Bob to answer any questions regarding his presentation and for everyone else to ‘catch’ up with each other regarding what they had been doing. The second half of the meeting there were some announcement regarding coming events, one of which was the proposed Perseid and Pizza night following Saturday (see report next page) and notice was given concerning the partial penumbral lunar eclipse in September. There followed some recent images taken by members. Chris Pennells had some recent images of the waxing and waning moon and some shots of the large sunspot group in July. Steve Goddard also showed some lunar images and some deep sky images that he had been taking, including the Crescent Nebula (NGC 6888), Ring Nebula M57 in Lyra, The Hercules Globular Cluster M13 and M51 The Whirlpool Galaxy in Canes (image top right.)
Maximum above and minimum below © Alex Vincent
The cause of the variability in this star is due to a close binary companion. It is believed the stars are locked tidally and the magnetic fields of the stars interact causing large ‘star-spots’ on their surfaces which cause the fluctuations in brightness that are observed. In answer to a question Alex said that it was possible to study photographs of variable stars and measure the relative brightness of them. An interesting meeting.
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The Southern Astronomer No.96 – September 2016
METEOR OBSERVING:
PIZZA & PERSEIDS NIGHT
U
sing a successful idea borrowed from our colleagues at HantsAstro, we held a club observing night styled a Pizza and Perseids observing night when we could get a a chance to meet up and do some astronomy – if the weather was kind – and so it was on the evening of August 13.
in the various aspects of practical hands-on astronomy – from naked-eye observing to scanning the night sky with a variety of differing kinds of instruments and varying types of manual and automatic (computer controlled) mounts. Mars, Jupiter and the Moon were observed as well as a number of meteors – some quite likely not Perseid but sporadics or even perhaps, some kappa-Cygnids.
The main meteor shower had passed about 24 hours previously with many members observing large numbers of meteors and some of them being captured on camera. Christine Parfitt observing the previous night had counted 15 in the space of about 10 minutes, underlining the fact that this years Perseid shower was going to be a bit of a storm.
There were of course a large number of faint objects slowly arcing across the sky – artificial satellites. Some were moving east; some westerly while others moved north to south and even some which went south to north.
© Robin Durant
© Rob Aro
Around the peak of the Perseid shower, a good many members took their chances and pointed their cameras to the sky and some were lucky as you can see here on these pages. Many took hundreds of frames with the result of only one meteor being captured – while some still caught nothing – thank goodness for digital imaging!
© Robin Durant
A thank you to all those who supported the evening and to those who bought along surplus pizza, hot sausage rolls, and delicious soup (well done Graham Williams). Let’s see if we can get another evening like that underway again, soon. © Jason Howells BH
The P&P night was pretty well attended by members from both WA and Worthing Skywatchers. It is quite fascinating to learn how many people are interested
NEXT WORKSHOP: OCTOBER 7
Our next Workshop is on the evening of October 7 – the day before International Moon Observing Night. There are some interesting presentations set up which I am sure everyone will find interesting, especially those who take pictures of the night sky. There is one other duty however that needs to be performed that evening and that amounts to a few minutes (I promise) house keeping duties – basically our annual general meeting (AGM.) It was Thomas Paine who once wrote, "That government is best which governs least.” What he was saying of course was the less a government interferes with the running of things, the better it is for the governed. I believe the same might be said of organisations too! I know of an astronomy group in southern England where the constitution of the group is tied up in 17 pages of tightly written rules and regulations. The ruling council (I use the nouns deliberately) even have a clause where they can initiate 'special powers' for themselves, to run the group in any way they wished if necessary without resort to consultation to the members. Their constitution is far larger and detailed than that of some nations! If their membership are happy with it, then so be it (though, to be fair, their membership is far less than ours!) I am rather proud of the fact that our own constitution, our Group Guidelines, is on just ONE page. When Worthing Astronomers was formed, the Guidelines were put into place so we had a frame work to which the group could be run but it was kept simple - we are an astronomy group, not some haggard back water, third world dictatorship. One of our basic tenets is that the group is run by the members, for the members. We have no formal committee, though we have a Treasurer who keeps the accounts and several other volunteers who ensure the smooth running of things - the co-ordinator who is the front end link for new members and public enquiries, organising Workshops, finding insurance, and generally publicising the groups activities; a web site editor who looks after the groups connection with the world wide web; an editor of this newsletter which keeps the membership informed and advised as to group activities and what is happening of astronomical interest in the skies for the coming month; and others who organise practical observing sessions for both the group and public observing - their work is so, so important. The statement of account will be given by Jan Halls our Treasurer – probably the most important job of the lot. As I described above, Worthing Astronomers is run by the members for the members. Now is the chance for you to have your say regarding how things are run – for example, would the needs of WA be better served by a proper elected committee; how would you like the Workshops to evolve - more theoretical astronomy or is the present balance of practical hands on astronomy the way to go. Would you like to help out. Keep things as they are? Have a think about all these things - it is YOUR astronomy group. Contact us at info@worthingastronomers.org.uk
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The Southern Astronomer No.96 – September 2016
Graphic: Stellarium
An all sky view September 15 at about 21.30 UT
The Milky Way remains nicely displayed in the mid-evening sky. The densely packed area of the Milky Way out towards Sagittarius is now beginning to set about this time but it will be visible – with a good horizon – a little earlier. Some members have taken amazing images of this region over the summer months. The Summer Triangle asterism comprising the bright stars Altair, Deneb and Vega is still very prominent reminding us that this is the late summer/early autumn time of the year. Overhead, M31 the circumpolar Andromeda Galaxy is well placed and remains so well into the new year. The view of the night sky above shows a nearly Full Moon – the bright light of the Moon mid-month may dazzle out some fainter objects until after moonset which occurs after midnight. Low in the south – so you will need a clear southern horizon - is one of the brightest stars in the sky, Fomalhaut in the constellation of Pisces Austranus. Laying at a distance of about 25 light years this second magnitude, triple star star is known to have a planet in orbit around it which was discovered in 2003.
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