Comet 2013 A1 Siding Spring. 18 June, 2013.
Combination of 5, 3 minute images unfiltered.
SBIG STL-1001E CCD. 300mm f/6 newtonian at prime focus.
Comet 2013 A1 Siding Spring caused considerable excitement when its orbit was first calculated, as a collision with the planet Mars appeared possible! Subsequent observations ruled out a colision, with a minimum approach distance of about 130,000km expected. While this was sufficient for the nucleus to miss the planet, it is still well within the coma. Special percautions were taken to ensure that all orbiting spacecraft would be behind Mars at the time of closest approach to minimise the possibility of damage from dust particles ejected by the comet. At the time of writing this, there is still a week to go before the encounter and there is still considerable excitement and interest in the encounter and what we might learn from it.
The comet itself has been difficult to observe from the northern hemisphere due to tis far southern declination. My only image to date came while I was in Australia.
