WADHURST ASTRONOMICAL SOCIETY

JUNE  NEWSLETTER  2004

INDEX: MEETINGS, OTHER NEWS, CONTACTS

MEETINGS

LAST MEETING

 The Transit of Venus and Astrophotography

Given by Mike Maunder on Wednesday 19th May 2004

Mike Maunder is well known for his astro-photographs that have appeared in magazines and newspapers around the world and his talk was mainly about this work with his camera over many years, but he began by referring to the forthcoming transit of Venus on the morning of the 8th of June 2004.  He mentioned a website www.sunearth.gsfc.nasa.gov containing a lot of information for the observer.  Also pointed out was that there was an occultation of Venus by the moon on 21st May 2004.  (Of course, by the time of this Newsletter, the Transit of Venus will already have taken place)

This will be the first time that the transit of Venus will have been recorded on film as the last transit of Venus was in 1882. [Link here to see it if you missed it!]

Mike then asked if we could see the link between a bottle of beer, a Channel Island one-pound note and a china mug, and "who we would phone as a friend" to find the answer?

The first photograph was taken by Thomas Wedgwood as early as 1795 using silver salts.  This method was used by Humphry Davy to take the first photograph of the sun using a solar microscope whilst he was Director of the Royal Institution.  The process used wet plates and was impractical to record permanent photographs.  Wedgwood was the link with Mike's china drinking mug.

The link between the Channel Islands pound-note was through the printer Thomas De La Rue.  His son, Warren De La Rue made his name through his work with the faster wet-collodian photographic process taking highly detailed photographs of the moon.

Finally, the link with the beer bottle was the beer inside it.  Sir William Abney used the beer-albumin dry plate process to make more practical photographic papers.  He made use of these emulsions to make solar photographs and did a lot of work on photographing the solar spectrum.  Mike also mentioned the son of William Herschel, John Herschel, who assisted Fox-Talbot by suggesting that he use salts to fix his photographic plates.

After this short history of the development of photography, Mike illustrated the remainder of his talk using his superb 2-inch by 2-inch square large format slides and began by showing us a colour chart which he photographed on each reel of film he took so that there was a reference after processing.

The first slides showed the effect of sodium light pollution, and then compared it with a slide taken of the southern sky from Australia.  There the skies were so dark, it was difficult for the observer to navigate around the stars but was easy to see the different colours of the stars.

Many of his slides had been taken from his home on Alderney in the Channel Islands, where the skies were relatively clear, although there was some pollution from the nuclear reprocessing plant on the north France coast when looking south.  Mike said that the green flash at sunset could be seen most nights.  Here on Alderney there are very few laminar flows (air cells) to cause aberrations, and he showed some superb slides of the silhouetted horizon but including Venus, Jupiter and Mars at dusk.  Most of his slides were wide angle and even one photograph used a fish-eye lens to include Hale-Bopp and Mercury on the same frame and taken in 1997.  The film he nearly always uses is 100 ISA Fuji Film, but not exclusively.

Most of the slides Mike showed from then on were mainly of scenes that included the planets and terrestrial landscape in the same picture.  There were some incredible sunsets and dawns, particularly at the times of volcanoes.  One series of slides were taken in Antarctica where Mount Erebus at the western end of Ross Island in Antarctica, close to the US McMurdo Research Station, was seen to be active most of the time.

A number of the slides were of the various solar eclipses observed by Mike throughout the world.  These included Kenya in 1980, Santorini, Greece in 1986, Arizona in 1994, India in 1997 accompanied by Patrick Moore and also where he was able to include Mercury and Venus.  Then of course, Alderney in 1999, although slightly cloud covered.  He had devised cameras to fit on each eyepiece of a pair of large binoculars, and then showed how he had balanced two small refractors on a tripod to obtain stability.

One slide demonstrated the dappled effect caught on the ground of the light from the approaching eclipse passing through the foliage of trees.  Something many of us, who have witnessed solar eclipses, forget to do.

Finally Mike Maunder finished with his famous montage-photograph of a solar eclipse taken every ten minutes before and after totality, with himself in the last exposure, "holding" the sun between his thumb and first finger.

In giving thanks for talk and the remarkable and colourful slides, our deputy chairman Michael Harte suggested, in answer to Mikes original question at the beginning of his talk, "Whom would we phone as a friend?" - we would phone Mike Maunder!

NEXT MEETING

The next meeting of the Wadhurst Astronomical Society is a Member's evening and will be held on Wednesday 16th June 2004.  This is an evening when members can give a short talk on a subject of their choice, which they think may interest fellow members.  These can be anything from ten minutes up to about twenty minutes in duration.

Two members have already volunteered to give a talk.  Joan Grace is talking about the Sun, a subject she has recently been studying, and Mike Wyles tells of a recent visit to Paris.  He might mention French food, but I think Astronomy is much more likely.

Tuesday morning, 8th July has turned out to be an excellent morning for observing the Transit of Venus for members able to do so.  If any members do have any photographs of the event, please bring them along.  I'm sure members would be very interested to see them.

As usual, the meeting will be held in the Drama Studio at Uplands College.  The doors open at 7.15 and the meeting starts at 7.30 prompt.

GO TO INDEX  

OTHER NEWS

THE JULY MEETING

At the July meeting, Murray Barber will be using the Starlab planetarium and demonstrating new innovations in mobile planetarium technology.  Specifically, the new FibreArc light source and Multilens cylinder.  The star effect is very different to the normal Starlab projector and Murray hopes to demonstrate a direct comparison which is very marked.

Sadly, this will be the last meeting that Murray will be able to Chair due his increasing commitments outside the Society, as mentioned in the last Newsletter.  It is important that we find a member prepared to take on the task.  They would not be expected to take on the role for as long Murray has been doing it by any means, but we do need someone ready for the September meeting.  Murray has said that he is very willing to talk about the position to anyone interested in finding out more.

GO TO INDEX

CONTACTS

Chairman:      Murray R. Barber               01892 654618      murray.barber@virgin.net

Secretaries:  Steve Camp       steve.camp52@btopenworld.com

                  Doug Biswell           dougrbiswell@aol.com

Treasurer:      Ian Reeves                        01892 784255

Membership Sec:   Joan Grace             01892 783721

Editor:           Geoff Rathbone                01959 524727         Geoff@rathbone007.fsnet.co.uk

Publicity & Web Site:      Michael Harte       01892 783292        michael@greenman.demon.co.uk

Dir. of  Obs:  Sean Tampsett                01892 667092        sean_tampsett@hotmail.com

  Copy for the July Newsletter should be with the Editor by June 30th  2004

GO TO INDEX