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Phobos (moon)

Phobos is the larger and innermost of Mars' two moons, and is named after Phobos, son of Ares (Mars) from Greek Mythology.

Phobos orbits closer to a major planet than any other moon in the solar system, less than 6000 km (3728 miles) above the surface of Mars, and is also one of the smaller known moons in the solar system.

Its systematic designation is Mars I.

Phobos orbits Mars below the synchronous orbit radius, meaning that it moves around Mars faster than Mars itself rotates.

Note:   The above text is excerpted from the Wikipedia article "Phobos (moon)", which has been released under the GNU Free Documentation License.
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