Archive for January, 2011
February Meeting Reminder
Sunday, January 30th, 2011
Don’t forget that the February meeting is this week, Wednesday 2nd February. Mike Nichols will give a talk called "Astro Navigation in Aviation". Mike learnt to navigate by the stars when he was in the RAF (before GPS was invented!) and he will describe the history and techniques of astral navigation.
Please note that the venue for this (and next month’s) meeting will be the function room of the Conservatory, Chequers Lane, Papworth Everard (see the map above). As usual we will start at 7.30pm.
Prof Alan Aylward – “From Daedalus to Dan Dare to Daedalus: Can we go to the stars and what would we find if we get there?”
Wednesday, January 12th, 2011
The New Year got off to a good start with a talk from Professor Alan Aylward (shown on the right in the photo above) who kindly came all the way from Surrey to visit us. Alan is head of the Atmospheric Physics Laboratory at University College London and gave us an overview of intergalactic space travel coupled with some of his research on the atmospheres of extrasolar planets (hence the atmospheric physics). He started by reminding the older club members about the spaceships used by Dan Dare in the Eagle comics of the 1950s. The idea of travelling the gigantic distances between our planet and other stars seems fanciful, but the comic book rocket actually has features that make it possible to do this, at least in theory. The basic concept involves the use of nuclear detonations to create a massive thrust that propels a spacecraft up to around 12% of the speed of light. This would be sufficient to send astronauts to a nearby star within a fifty year time frame. This idea was seriously considered by the British Interplanetary Society in the 1970s and NASA up to, and including, the present day. The project was seen to be feasible in engineering terms, but the original idea of using nuclear fusion by lasers has been subsequently shown to be impractical (at least for now). There are of course all sorts of unanswered questions, not least those relating to the fate of the astronauts who may be travelling on a one way ticket to the stars.
Other propulsion systems were described, including a giant earth-based laser that would be shone onto a lightweight sail attached to a spacecraft. These and many other ideas are being actively considered by NASA who stipulate that any proposal must keep to the laws of conservation of energy and of momentum; this is apparently something that even the best scientists get caught out with!
So having discussed travel to the stars, Alan described how it might be possible to detect habitable planets around these stars. His research group in London studies the atmospheres around exoplanets (of which most appear to be smaller than Jupiter-sized objects). The number of such planets is increasing on an almost daily basis and it is possible to observe their effects on their parent star even using the venerable telescope at the Mill Hill Observatory in North London. This is quite a testimony to the equipment and data analysis capabilities of the exoplanet research group, since this part of the UK suffers from serious light pollution. Nevertheless, data are being gathered that allow astronomers to make inferences about the types of molecules (including the all-important water) that is present in the atmospheres of possible earth-like planets. The discussion about extraterrestrial life is now getting sensible, as experiments are underway to get real evidence, rather than just rely on speculation about what might be. Maybe this is a good omen for astronomy in 2011.
The meeting was publicised as part of the BBC’s Stargazing Live programmes that were broadcast in early January. We were delighted to see several new faces at the meeting as a result of the publicity and we hope to be able to be of assistance to several members who have bought a telescope for the first time.