Nasa s extensive fleet of science assets particularly those orbiting and roving mars have front row seats to image and study this once in a lifetime flyby.
Comet siding spring buzzes mars.
Hubble images show comet siding spring has passed the snow and water lines the points at which the sun s warmth activates or releases gases and water ice to form the coma and tail.
Initial observations by leonid elenin on 27 february 2013 suggested that it might pass 0 000276 au 41 300 km.
Comet siding spring will approach within 86 000 miles 138 000 kilometers of mars on oct.
Comet siding spring s dust tail will completely engulf the entire planet when mars travels through it.
But the dust shed by the comet.
Comet siding spring passed extremely close to mars on 19 october 2014 at 18 28 0 01 utc.
19 comet c 2013 a1 comet siding spring will pass within about 87 000 miles 139 500 km of mars.
Spacecraft at mars might get a good look at the nucleus of comet.
86 500 mi from the center point of mars and the uncertainty region shows.
In october comet siding spring will buzz mars at 125 000 miles per hour and close enough for the comet s tail of gas and dust to envelop the planet.
With an observation arc of 733 days the nominal pass is 0 000931 au 139 300 km.
On that date comet 2013 a1 siding spring will buzz mars about 10 times closer than any identified comet has ever flown past earth.
19 potentially putting on a good show for nasa s red planet spacecraft.
In a rare cosmic close encounter the comet siding spring whizzed past mars at a distance of 139 500 kilometres just more than one third of the distance from earth to the moon on 19 october.
25 700 mi from the center of mars.
The comet siding spring whizzed within 87 000 miles of mars close enough for nasa to force its fleet of spacecraft orbiting mars to duck for cover.