|Discovery date||18 August 1877|
|Discovered by||Asaph Hall|
Phobos is a heavily cratered potato-shaped moon with a prominent crater near one end. The crater is named Stickney. One orbit of Phobos around Mars takes 11.1 hours which is nearly three times shorter than Mars' other moon, Deimos, which takes 30.4 hours to orbit Mars once.