Mars' Moons

Mars has two small moons, Phobos and Deimos. Phobos is the larger of the two. It is shaped like a potato, about 15 miles long by 10 miles wide. One end is scarred by a giant crater. The impact that created it may have fractured the entire moon, leaving big cracks that travel from one end to the other. Phobos is in such a low orbit that it circles Mars about three times per day. It rises in the west, then sets in the east just a few hours later. As seen from the equator it looks less than half as big as our Moon looks from Earth. Deimos is both smaller and farther out. It takes almost three days to complete one orbit. From the Martian surface, it looks about like Venus looks from Earth.


Mars' Moons Two small moons, Phobos and Deimos, orbit Mars....
Mars Mars inspires speculation like no other world in...

Radio Programs

Moon and Planets Profiling undiscovered moons Sunday, September 28, 2014
Mars Companions Distant companions for the Red Planet Sunday, December 1, 2013
More Moon and Mars Taking a ride on a Martian moon Sunday, January 13, 2013
Phobos-Grunt DNA testing for a Martian moon Friday, November 4, 2011
Moon and Mars Twin moons under alien skies Thursday, September 22, 2011
Birth of a Moon New ideas about the birth of a moon Friday, April 15, 2011
Martian Mayhem A violent birth for a Martian moon Thursday, November 11, 2010
Moon and Companions Picking blueberries...on Mars Wednesday, June 16, 2010

Featured Images

High-resolution view of Phobos, moon of Mars
Doomed Moon Sunday, January 13, 2013
The Russian Phobos-Grunt Mars mission launches on November 8, 2011
Phobos Flop? Friday, November 11, 2011
The moon Phobos floats above Mars
Martian Target Thursday, November 3, 2011
Phobos, one of the moons of Mars, passes by the planet Jupiter.
Out of Order Monday, June 20, 2011


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