May 2006 Meeting

The 416th Meeting of the Altrincham and District Astronomical Society, held at Timperley Village Scout hut on Friday 5th May 2006 at 8pm

Those present were:
Paul Clark, Kevin Thurstan, Mark Crossley,
Tony Aremia, Philip Masding, Don Utton,
Norman Thurstan, Colin Eaves, Geoffrey Walton,
Graham Sinagola, Nick Dixon, Ged Birbeck,
John Tipping, John Gartshore, Roger Livermore,
Stuart Oldbury, Paul Brierly, Chris Suddick,
Peter Baugh, Richard Bullock.

(Total 20)

The chairman Paul Clark opened the meeting by welcoming everyone and apologising for being late. He then thanked everyone who had helped sort out for tonight’s new venue, announcing that tonight we would start with a talk by Phil Masding called spy satellites.
Phil started by saying, “Lets see what we can find in the public domain”.
First Is the International space station, “ been there, seen that, got the T-shirt”.
What else can you see? All the rest are very small in comparison, the next largest is the European satellite Envisat, however some of the others he has been trying to observe are the US Lacrosse satellites.
The orbits for these 5 satellites are not published by the US and the orbits are only known because of amateur observations. He told us that given just a few observations from around the world that it was quite easy to calculate a satellites orbit.
We were then given the known details on the satellites & their side looking radar systems.
Phil then detailed his own successful attempts to image some of them, and using software he wrote himself, to use those images to work out some of the satellites true dimensions.
Using his new diffraction grating he has now taken the spectrum of a different satellite, which may be an amateur first.
The secretary thanked Phil for his talk and the meeting had a tea break.
When the meeting resumed Mark Crossley gave us an update as to what has been happening with comet 73P and showed us some images of it taken by himself prior to it’s latest break up.
After thanking Mark the secretary started on club business :-
The society’s application to the Timperley village fair was being sent.
The society now has a copy of David Ratledge’s new book for it’s library, and the society has received £50 from the Forestry Commission for our March talk at Delamere.
Ged has received a quote for clearance of the obs site of £3000 and we are still waiting for a quote from the council themselves. It was suggested that we may hold a working party in June or July to do some of the work, fair warning was given “if it’s yours – take it out or it will be cleared”. It has also been confirmed that we do not need an asbestos survey.
Next were opinions on the new venue, the general consensus was good.
Chris Suddick told us the Adas website was up for renewal and he would do this for 2 years.
Paul Brierly suggested we might wish to join him on the 19th/20th May at Clough House, possibly our last chance to observe galaxies until after the summer.
Tony Aremia thanked everybody for his card and their kind thoughts.The meeting was then brought to a close.

The 415th Meeting

The 415th Meeting of the Altrincham and District Astronomical Society, held at Timperley Village Club on Friday 7th of April 2006 at 8pm

Those present were:Paul Clark, Kevin Thurstan, Mark Crossley,Richard Bullock, Colin Eaves, Geoffrey Walton,Graham Sinagola, Nick Dixon, Ged Birbeck +2, Chris Suddick, Peter Baugh, Don Utton,Philip Masding Roger Livermore B Hetly ? 1 other,(Total 18)

The chairman Paul Clark opened the meeting by welcoming everyone to the 415th meeting and announced that tonight we were fortunate to have David Ratledge from Bolton AS to give a talk on advances in digital astrophotography. David started by explaining how CCD chips work. He told us some of the advantages of silicon over film were that silicon is ten to twenty times more sensitive, no reciprocity failure and substantial subtraction of light pollution. David then talked about web cams. They are cheap but you need a laptop or computer to run one. They are good for imaging the Moon, planets, sunspots and can be used for double stars.

Next was the digital darkroom he said that he used Iris software which is one of the ones that is free on the internet and that using parts of it he could get two to three times more resolution in the final image which was good for galaxies and planetary nebulae. We then heard about infrared imaging. Infrared imaging done through black glass cuts out all light pollution and penetrates the Milky way’s dust clouds, allowing you to see through the Milky way to otherwise hidden galaxies. It also lets you image quasars and the early universe.

His next topic was digital SLR cameras. One advantage is that they have big CCD chips, in fact the same chip is used in some £500 DSLR cameras as in some £4000 dedicated astro CCD cameras. However they do have some problems of their own, they are poor at the red end of the spectrum as they have a filter over the CCD chip to give better flesh tones, but you can get one over the internet where the filter has been replaced with a clear one. Other problems include generally coming with poor quality lenses, exposure noise, dewing up and difficulty aiming through the viewfinder.

Lastly he spoke about hybrid images where a close up image was pasted onto a wide field image for a more detailed composite image.

We were shown lots of great images throughout the talk and were told if we wanted to see more to visit his website at www.deep-sky.co.uk. Paul thanked him for his talk and we then had a break.

On resuming the meeting Paul Clark showed us four images of Saturn through his 6” scope with a webcam, to show his improvement over the last month. He then talked briefly about the viewing possibilities for the fragmented comet 73P/Shcwassmann-Wachmann over the next couple of months. Following this we went onto society business. The Secretary noted that we had received the new BAA journal and thanked Paul Brierly for donating a book on the moon for the society’s library. He also thanked all those who went to help and support at the recent astronomy evening at Delamere Forest Park. Ged Birbeck reported that as yet we had no prices for the clearing of the obs site. It was stated that there was a card for Tony Aremia, who was in hospital, for anyone who wished to sign it and had not yet done so, sending him our best wishes.

For our next Meeting, on May 5th at 8.00pm, we would be changing venue and trying out the Scout hut. The meeting was then brought to a close.