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Mars Moons

Mars has two moons, Phobos and Deimos. Both are believed to be captured asteroids.

IAU Number	IAU Name	Discovered	Discoverer
Mars I	Phobos	1877	A. Hall
Mars II	Deimos	1877	A. Hall

Phobos is the larger of Mars' two moons. It orbits Mars three times a day, and is so close to the planet's surface that in some locations on Mars it cannot always be seen. Phobos is nearing Mars at a rate of six feet (1.8 meters) every hundred years. At that rate, it will either crash into Mars in 50 million years or break up into a ring.

Deimos is the smaller of Mars' two moons. It orbits Mars whirls around Mars every 30 hours.

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