Fact Sheet
Moons of Mars
American astronomer Asaph Hall discovered the moons of Mars 125 years ago this week. Phobos, shown in this image from Mars Global Surveyor, is the larger moon. Like that of its smaller sibling, Deimos, its surface is covered with impact craters. The largest crater, at top left, is about six miles across and is named Stickney, the maiden name of Asaph Hall's wife. [Credit: NASA/JPL]
|