Comet almost crashes Mars Sunday October 19th.

An Oort cloud comet, "Siding Spring"is missing Mars by a whisker on Sunday, by a mere 87,000 miles.  The planet will get a small dusting of carbon compounds and water vapour.  A little closer and it could have dumped enough stuff to restart a robust atmosphere..  Mars orbiters plan to duck and cover on the other side of the planet about an hour and a half after the nucleus passes to hide from the debris trail. Meanwhile both orbiting sun observatories and other devices will scoop data.
Science Daily News.

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