Comet’s Close Encounter with Mars Dumped Tons of Dust on Red Planet

Sebastian Voltmer in Germany used the iTelescope at Siding Spring Observatory, Coonabarabran, New South Wales, Australia to capture Comet C/2013 A1 passing very close to Mars on 19 October 2014. He used their Takahashi FSQ ED refractor and SBIG STL11000M camera for four 120-seconds exposures; RGB 120-seconds (Bin 2). Image credit: © Sebastian Voltmer.


Comet Siding Spring’s close shave by Mars last year provided a rare glimpse into how Oort Cloud comets behave, according to new research.

The comet flew by Mars at a range of just 83,900 miles (135,000 kilometers) — close enough for the outer ridges of its tenuous atmosphere to pummel the planet with gas and dust.

In just a short flyby, the comet dumped about 2,200 to 4,410 lbs. (1,000 to 2,000 kg) of dust made of magnesium, silicon, calcium and potassium — all of which are rock-forming elements — into the upper atmosphere, the new study found.