AAS

Our inaugural meeting was on the 8th November 2010 and we officially formed in February 2011.
AAS holds monthly meetings with guest speakers.

All guests are welcome!
No knowledge necessary, just a curious mind.

We are able to provide assistance with setting up your telescope or just helping to find your way around the night sky.

AAS is able to host discussions on subjects as varied as Dark Energy through to 'How dark is your sky'.

Come along and get a new perspective on the universe in which you live!

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Last Meeting 13th November

A good session last Monday, when Nick highlighted key facts about our nearest star, the Sun.  The “News of the Month” presentation has been put on the “Downloads” page. HERE

Artist impression of the dust clouds around Proxima Centauri  :  credit ESO/M Kommesser

One question that generated discussion but no definitive answer related to the travel time for a probe sent to our next nearest star, Proxima Centauri, around 4.2 light years distant.  The question arose from the concept proposal by “Breakthrough Starshot” ( HERE & HERE ) to send a swarm of small space craft at 15/20% of c, the speed of light, to collect data and image the Proxima system, including the exo-planet Proxima b.  Travel time would be of the order of 20/30 years. 
Specifically the question was what effect would travelling at 0.2c have on the different time frames of Earth and the probe.
I have put a graph of time dilation vs speed on the “General Items” page.  The conclusion is that at 0.2c the time dilation is such that the time on the probe would be running 2% slower than time on Earth, so 20 years on earth will be equivalent to 19.6 years on the probe.

Note:- Maximum speed reached by the Cassini probe on its way to Saturn was 44 km/s, or 0.00015 c.  At that speed it would take 29 thousand years to reach Proxima!

However, it would seem that we wouldn’t want to go to Proxima b anyway due to the significant radiation from its host star, a red dwarf.  It now seems that a better bet would be Ross 128 b, which is only 11 light years away, or 55 years at 0.2c.  OK for our younger members but a bit too long for me to see any results!!

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