This graphic depicts the orbit of comet C/2013 A1 Siding Spring as it swings around the sun in 2014. On Oct. 19, the comet will have a very close pass at Mars, just 86,000 miles (138,000 kilometers) from the planet. Although the nucleus will miss the planet, the comet's coma of dust particles might envelop the Red Planet.
More info at: http://mars.nasa.gov/comets/sidingspring/
Image Credit: NASA/JPL-Caltech
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