The Southern Astronomer - newsletter of Worthing Astronomers

The Southern Astronomer No.67 – April 2014

SOUTHERN ASTRONOMER THE

NEWSLETTER OF WORTHING ASTRONOMERS & WORTHING SKYWATCHERS

NATIONAL ASTRONOMY WEEK Report

This issue NAW Report & Gallery Workshop & Sun Day News Items Jupiter Shadows Observing Notes For Sale

this page and pages 2 and 3 page 4 page 5 page 6 pages 6 – 8 page 9

Astronomy Meetings All the meetings listed below begin at 19.30hrs BST Worthing Astronomers (WA) meet on the first Friday every two months (February, April, June, August, October and December); April, we will be at the Goring URC, corner of Shaftsbury Avenue and Barrington Road, Worthing, BN12 4EA. Admission £3.

National Astronomy Week is not a regular event so when it comes along we take the opportunity to take our telescopes onto the streets of Worthing and show the public the wonders of the night sky.

The evening of March 7 did not look to hopeful as the weather forecast was cloud and fog.

The combination of two of astronomers' enemies did put an early end to our first NAW night but not before 50 or so members of the public turned up got some beautiful views of Jupiter and the Moon – the light mist having a calming influence of the seeing. Over a dozen members of WA and Worthing Skywatchers with their telescopes turned up and members of the public – as far as Yapton and Brighton brought theirs. Quite a few new members were signed up that night as well.

Adur AS (AAS) meet at Southwick Christian Community Church, 1-5 Roman Crescent, Southwick BN42 4TY.Admission: £5 for guests, £3 for members.

Foredown Tower Astronomers (FTA) at Emmaus Charity Premises, on the corner of Manor Road and Drove Road, Portslade Old Village, BN41 2PA. Admission £3 for guests.

Worthing Astronomical Society (WAS) meet at Emmanuel URC, St.Michaels Road, Worthing BN11 4SD. Admission: £4 for guests.

AAS, FTA, and WA venues have off road parking facilities and grounds adjacent for setting up telescopes when conditions allow.

WA members will always be made welcome at these groups. More information 01903 521205 or 07801 692244.

Fuller details of what our colleagues in neighbouring societies are doing at their monthly meetings is in the Quick View Diary, page two, Worthing Astronomers is a free to join society with a membership of over 300, all interested in the same hobby of Astronomy.

With the aid of this newsletter, 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.

Above: The start of the evening of the 7th – set up.

Picture: Mike Williams

The following day, was a much finer day weather wise with a forecast promising good weather for the evening.

The telescopes were relocated up to the beach wall – some Lycra clad loons (cyclists) using the promenade had proved to be a hazard on the Friday night – not slowing down when they saw pedestrians in their way for example; don't these people read the Highway Code? The beach wall turned out to be ideal for locating support equipment.

The night, as predicted by the weather forecasters was indeed a fine and clear night with a bright first quarter Moon, Jupiter and a host of deep sky objects that were available for the public to look at through the varying selection of 28 telescopes present, to look through.

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The Southern Astronomer No.67 – April 2014 Continued

An estimated 200 or so members of the public popped along over the evening to take advantage of the telescopes and views of the night sky.

Though the GRS on Jupiter was not visible, Lunar X made a guest appearance as did the Lunar V. Later in the evening we got to see Mars rising in the south-east.

QUICK VIEW ASTRO EVENTS DIARY

April All times shown are Universal Time (UT = BST minus 1 hour)

Above: Chance alignment of shadow of the early morning lunar sunrise highlights strange topographical features – the X and V features on the lunar landscape.

Photographs: Gary Isherwood Below: This event saw the use for the first time our use of hi-vis jackets with 'Worthing Astronomers' embroidered on the back to help the public identify telescope operators.

1 - Sunrise 0539h : Sunset 1836h 4 - WA: Workshop - Observing Planets St Audries Bay Star Party start 5 - Global Star Party: GAM global observing event 6 - Jupiter 5.3°N of Moon (21h) St Audries Bay Star Party ends 7 - Moon: First Quarter (08h) AAS: guest speaker, Ninian Boyle 8 - Moon at apogee (15h) Mars at opposition (21h) 10 - Regulus 4.9°N of Moon (22h) 14 - Mars closest to Earth (14h) Mars 3.3°N of Moon (15h) WAS: Exploring The Solar System with Robots 15 - Full Moon: lunar eclipse (07h) – eclipse occurs after Moon-set 17 - FTA: Restoration of The Greenwich Time Ball 22 - Lyrid Meteor Maximum (pre-dawn) Moon: Last Quarter (07h) 23 - Moon at perigee (0h) 27 - Sun Day: GAM Solar Observing Day 29 - New Moon (06h) 30 - Sunrise 0439h : Sunset 1923h FROM THE ARCHIVE April 2009: As part of National Astronomy Week which was coinciding partly with the International Year of Astronomy (IYA), members went down to Splash Point on the promenade as part of a 'Moon Watch Week' from March 28 to April 5.

More pictures, next page

The National Astronomy Week organizing committee handed out grants for astronomy groups like ourselves and Steve Bassett applied on our behalf for a grant – and the application was accepted with a grant of £50 being awarded. This will go towards the purchase of materials (like hi-vis jackets for example) that will help us do public out reach events such as the observing we held on the promenade. Many thanks, Steve.

Suggestions for other public observing events are always welcome.

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This was the first public observing session to be held by the fledgling WA and it was a success, though turning up at Splash Point every night for over a week was exhausting.

Many members of the public returned night after night (when weather allowed) to see the lunar shadow crossing the face of the Moon and presenting new features. Some of those visitors eventually became members.

The Southern Astronomer No.67 – April 2014

NATIONAL ASTRONOMY WEEK GALLERY Views of Stargazing On the Prom

A Saturday family night out.

Photograph: Della Griffith

The west end of the telescope line up

Photograph: Matt Maynard

Fishy tails. The one that got away - what is Graham Williams describing?

Photograph: Mike Williams

Many thanks to all those members who have sent in their photographs and images from the two nights – too many to publish in the newsletter all in one go though we shall keep them in the archive and may publish them in the future, both here and on the website.

There is also a very grateful thank you to all those members who took time out to bring their telescopes onto the seafront those evenings so they could share the views of the night sky with total strangers and to those members and their families who came down to support and help.

It showed that astronomy is far from a dull scientific subject pursued only by people in white lab coats on some far off hill top domed building.

Sophie Watts captured Lunar X and V imaged using just her camera phone placed next to the eyepiece.

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The Southern Astronomer No.67 – April 2014 GENERAL NEWS WORKSHOP EVENING Observing The Planets For those unable to get along to St Audries Bay Star Party, we shall, on April 4 be holding our Workshop evening – the one postponed from February – in the Cornwall Room at Anyone who watches TV may be familiar with Goring URC at 19.30hrs. The subject will be observing the planets. Brian Halls will start by the channel 'idents' – those little small pieces of briefly describing observing the planets at the eyepiece and our colleague John Bush who film that sometimes link programmes; you is also a member of Adur AS will be talking about imaging the planets.

THE MORE 4 ASTRONOMER

maybe familiar with the BBC swimming hippo's for example – that's an 'ident'.

Because of limited time the doors will be open at 19.00hrs to set up and we start at 19.30hrs sharp. We have to be out by 21.30hrs.

As usual there will be tea and coffee available, thanks to Chris Pennells. Chris has done this fine service since we began our Workshops over a year ago and so it would be nice if we could have a volunteer or two to give him a hand and perhaps rotate this vital service over the various meetings we have so it is not done by the same person all the time.

Drop us a line if you can help – info@worthingastronomers.org.uk.

Because of the new venue we are sorry to say that the entrance is now £3.

One of the idents used by TV channel More 4 is of an astronomer getting a telescope ready to do some observing (above).

The astronomer in question is astro-imager, John Slinn of the Facebook group, The Disciples of the Dark Arts (despite the spooky name, a group of dedicated deep sky imagers who produce some amazing images of deep sky objects (hence 'dark-art')).

John (who is also a member of WA), is one of the speakers at the St Audries Bay Star Party, Somerset, on April 4-6 (see back page)

Further Workshops suggested for the future are setting up and using a telescope and a back to basics introduction to telescope imaging using web-cams.

We will let you know the dates of these meetings.

SUN DAY Sunday, April 27 Global Astronomy Month is held annually in April and this year it seems that the event is being a little bit downplayed by the organisers – Astronomers Without Borders. One GAM sponsored event that we will be doing is Sun Day – a day dedicated to solar observing.

To see John in action on the ident, pop along to We have previously held this event at a back garden observatory so members can pop the Vimeo website - http://vimeo.com/18998930 along during the day and see how the Sun is observed in safety, via the projection method,

objective filters and in hydrogen alpha, have a cup of tea or something and have a chat.

Jan and Brian are opening their home (or more strictly their garden and observatory) to members and their families to come and have a look and see what is happening on the Sun that Sun Day. Members are welcome to bring along their own telescopes. In past years techniques and trouble-shooting solar observing problems have been discussed and members have got a better understanding of what solar astronomy is all about.

Why not pop along, have a cup of tea or something and have a chat. Times are 11 a.m. to 4 p.m BST. As is usual, this event is very much weather dependent – we will keep everyone posted as to availability. Contact details for further information – 01903 521205 or 07801 692244.

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The Southern Astronomer No.67 – April 2014 JUPITER DOUBLE SHADOW SATELLITE TRANSIT March 16 Members took advantage of the clear skies to get a view of the double shadow transit of two of Jupiter's moons across the planets disk.

As members set up for the evening observing, Andy Lee took a photograph of the Full Moon rising in the east – distorted by the atmospherics and looking a lot larger than it really is (the 'Moon Illusion') exaggerated even more by the foreshortening effect of the telephoto lens.

Above: At her home, Sinead Woods captured the two shadows (left side of planets disk) and the two satellites. Sinead used a DSLR, on her 20cm (8”) Dobsonian mount telescope at 2232UT. North towards upper right in both images.

Above: Steve got a view of a few of the telescopes in use during the evening.

SHADOW LAND – JUPITER SATELLITE SHADOW TRANSIT March 16

Above: On the prom, Steve Bassett view of Jupiter using a 15cm (6”) reflector and Phillips SPC900 webcam and 3x barlow.

Two satellites of Jupiter, Io and Ganymede had their shadows cross the face of Jupiter at the same time on the evening of March 16.

The shadow of the satellite Ganymede is the lower shadow while Io's shadow is the upper.

Half a dozen members met with their telescopes down on the seafront where we had held the popular and successful NAW event the previous weekend.

Io is actually in transit across the face of Jupiter (almost right of central), while Ganymede is the faint star like object to the lower right of the planet in the above images.

Though it was a long wait – the shadows did not start appearing until about 22.00hrs – it proved to be worth it.

Several members, unable to get to the seafront, were able to enjoy the spectacle from their own regular observing sites.

In Sinead's picture, Europa can just be seen faintly, top left.

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The Southern Astronomer No.67 – April 2014 OBSERVING NOTES April All times are expressed as Universal (UT) and can be considered the same as GMT (BST minus 1 hour)

With the Sun having crossed the celestial equator at the Vernal Equinox (March 20) the Sun is getting higher in the sky, with nights getting shorter and daylight getting longer; the night time amateur astronomer will still find plenty to see in the night time sky to interest them.

The Sun in March was again reasonably active – many small groups appeared. The large naked-eye sunspot group that appeared at the beginning of the year and a month later appeared once more at the end of February and into the start of March but had decayed considerably in size and activity and was no larger than some of the sunspots we have seen lately.

The WA relative sunspot number for the month (R) was 98. This is a slight increase over the figures we have seen over the last few months.

Brian States noted faculae (bright clouds of hydrogen visible in normal light) as very prominent on several days Above: Fila-proms on the eastern edge of the Sun and a large bright sunspot area from March 9.

Image Brian Halls during the month.

The Moon goes through a total eclipse on April 15 though this event occurs after moon-set from the UK. The early stages – the Moon entering the lighter penumbral shadow - occurs just 13 minutes before the Moon sets.

The BAA Lunar Section highlight some interesting lunar features to observe at certain times during this months lunar cycle. Further information may be had at the Lunar Section website: http://www.baalunarsection.org.uk/2014-03-lsc.pdf

ASTRO LINGO Fila-proms – a convolution of two words; filament and prominence, which to confuse matters are two words to describe the same phenomenon.

Prominences are the large gaseous arcs and clouds often seen at the edge of the solar disk – either during a solar eclipse or, as in the image in the picture on the left, seen through a hydrogen alpha telescope.

A filament is a prominence seen while it is on the disk of the Sun; again using the picture on the left, filaments are the dark streaks to the right of the bright sunspot area.

A fila-prom is part of a prominence on the edge of the Suns disk while the rest of the prominence appears as a filament on the solar disk.

Gibbous – when an inferior planet (Mercury, Venus) or the Moon shows a phase that is between half and full (e.g. 'waxing' Moon) or between full and half (e.g. 'waning' Moon).

Moon Illusion - is an optical illusion in which the Moon appears larger near the horizon than it does while higher up in the sky.

The same optical illusion can also occur with the Sun and some constellations. It has been known since ancient times and recorded by various cultures. The explanation of this illusion is still debated – atmospheric refraction is insufficient alone as an explanation; almost certainly it is an effect caused by the human eye and brain working together.

To shatter the illusion hold out a regular pencil at arms length at the larger than life Moon (or Sun if covered in haze or thin cloud near sunset) and the pencil will neatly cover the 'enlarged' object. The illusion disappears.

Lunar and planetary visibility mid-month

Several planets appear in the evening skies during the early spring, while the two inner planets, Mercury and Venus are visible in the morning sky. Mercury is poorly placed midmonth, rising a few minutes before the Sun.

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The Southern Astronomer No.67 – April 2014 Continued

Venus on the other hand is a bright object in the morning dawn. Now past its most westerly elongation, it has the appearance of gibbous Moon. It is still a nice size in the telescope, 22-arc seconds and thus is about half the apparent size of Jupiter when seen through a telescope, with a phase of about 60% mid-month.

Transits Times of the Great Red Spot (GRS) of Jupiter – best views from UK April 1: 2:52, 22:44; 2: 18:35; 3: - 4: 0:22, 20:14; 5: - 6: 2:01, 21:53; 7: - 8: 3:40, 23:32; 9: 19:24; 10: - 11: 1:11, 21:03; 12: - 13: 2:50, 22:42; 14: 18:33; 15: 4:29; 16: 0:21, 20:12; 17: - 18: 2:00, 21:51; 19: - 20: 3:39, 23:31; 21: 19:22; 22: - 23: 21:01; 24: - 25: 2:49, 22:40; 26: 18:32; 27: - 28: 0:20, 20:11; 29: - 30: 1:59, 21:50 All times shown are in UT Reproduced courtesy of Sky Publishing The GRS will be well placed for observing 50 minutes or so either side of the times given.

Rising in the evening sky Mars comes to opposition on April 8. Though nearer to Earth than Jupiter it is a much smaller world. At opposition (when it will be almost due south at midnight) it will be 15-arc seconds in size, shining at -1.5m. For moderate sized telescopes (10cm upwards) the surface features are always worth looking out for. Mars will be 5° north of the Moon during the evening of April 14.

Something to look out for; the red colour of Mars is highlighted by its close proximity to the blue star Spica. Binoculars may show it well. See what you think.

Jupiter still dominates the evening sky though it is now getting progressively further away from us. Its angular size is still a respectable 37-arc seconds mid-month. Reports previously in the newsletter mention the double transit of the shadows of the Jovian satellites Io and Ganymede on March 16. Earlier that evening, Ganymede had transited across the face of Jupiter just in front of the GRS; in a small telescope it looked like a shadow rather than the dark bodied satellite.

The satellites of Jupiter regularly cross the face of the planet as do their shadows (transits and shadow transits) and they can some times be seen to duck behind the planet (occultations). Times and dates for these events can be found on the internet or are available on request in a pdf format (see bottom, next page).

The next planet out from Jupiter, Saturn, rises mid-evening and remains low in the sky in the constellation of Libra. It comes to opposition in early May.

Have you thought of joining the BAA, the UK's premier amateur astronomy organisation?

Special deal: * 18 months' membership for the price of a year * February, April and June 2014 Journals FREE * NEW 72-page Observing Guide, worth £7.50, FREE This special offer is not available to existing BAA members.

Nothing more to pay until August 2015.

Offer closes 2014 June 30.

Click the link: www.britastro.org/join and join now.

Above: Schematic of Lyrid radiant.

The Lyrid meteors make their annual return to the skies near to the end of the month. The observing 'window' for this shower is April 18 to April 25 with an expected average hourly rate (ZHR) of 10. Maximum occurs at 17hrsUT on April 22, so though we will miss the maximum, observations prior to sunrise on that morning or the next morning will be best. It is considered by the BAA to be favourable hower.

There are no bright Comets visible during April though one comet is of 8m.

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The Southern Astronomer No.67 – April 2014

Image by Stellarium

The sky from Sussex at around 21.30 UT (22.30 BST) on April 15 Contributions – written articles (preferably word processed), photographs or letters to the editor for the April issue should be in by May 16 and sent to the editor at the contact address: editor@worthingastronomers.org.uk Detailed occultation predictions and other data in PDF format may be had by contacting the same address. (Please include exact latitude, longitude and approx height above sea level – these can be found using a service like Google Earth, for example.)

If you no longer wish to subscribe to the group and receive newsletters and other information, please send an email (to the address above) with Unsubscribe in the subject line; we do not want our stuff to end up like spam littering your inbox. 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.

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.

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The Southern Astronomer No.67 – April 2014

FOR SALE Vixen/Orion Telescopes Orion 300mm f4 (shown) and 150mm f8 Newtonian reflectors; single equatorial mount and stand plus Vixen Sky Scout guide handset to go with the telescope mount.

£350 o.n.o for two OTA, one mount, plus the Vixen controller.

Contact: jamie_maria@hotmail.co.uk (Seaford) for more details.

The mirrors on both 'scopes look a little tarnished (that's what mirrors do) but may be still quite usable.*

Is there anything you would like to see in The Southern Astronomer?

[I think this offer is worth a look at. Ed]

Have you been busy at the telescope drawing or, taking pictures.

Why not send them in?

*[Orion Optics (UK) are doing a special deal on mirror resurfacing until August 2014.Ed]

Have you an amusing astronomically based story you would like to recount?

Is there something you would like to say?

FOR SALE

Have you something for sale?

Two powerful cross haired optics originally fitted into a powerful Leica Total Station (modern surveying equipment the equivalent to a theodolite).

We can advertise your private sale free of charge – the newsletter is read widely (nearly a thousand reads a month for the online version alone)

May make good pocket telescopes £50 each

The Southern Astronomer is your newsletter – use it to reach out to your colleagues and members of other groups

Contact: Bob Turner at Rrfturner@aol.com

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The Southern Astronomer No.67 – April 2014

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