COMET SIDING SPRING SKIMS PAST MARS

Comet Siding Spring made a close pass by Mars on 19 October:
http://www.bbc.co.uk/news/science-environment-29665247

This was a unique event: the first time a comet from the Oort Cloud has been observed close to a planet. Since there are a number of observation instruments on the Martian surface and in orbit, this was in effect an outpost scientific observatory on Mars able to gather data on the comet's approach. Siding Spring passed 139,500 km from Mars.

The Curiosity and Opportunity surface rovers were trying to photograph the comet, while the Reconnaisance Orbiter and other satellites attempted to resolve the comet's shape, study its gas and dust shroud and the material trailing away, and examine any interactions with the Martian atmosphere.

The comet was first observed in January 2013 at the Siding Spring Observatory in New South Wales, Australia. It was possibly knocked from the remote Oort Cloud towards the inner solar system by a passing star. It is believed that the comet is very little altered from the time of its formation more than 4.5 billion years go, and may have been travelling since the dawn of man.

Comment: The initial photographs from Mars are historic but unspectacular. Hopefully detailed analysis of all the data obtained from the comet fly-past will reveal valuable scientific insight into this primordial comet. It is truly wonderful that all the instrumentation that has been placed on and around Mars has formed such a useful science laboratory outpost in place to study this unique event.