Phobos up close

Phobos up close
Phobos up close This image of the heavily cratered Phobos was taken by the Viking 1 orbiter in 1978. It is Mars’ largest moon and orbits the Red Planet about three times a Martian day, which is 24 hours, 39 minutes, and 35.244 seconds to be exact. Phobos orbits so close to Mars that it is doomed. The gravitational forces are tugging on it and slowly dragging it down. One day, millions of years from now, Phobos will likely “crash and burn,” said Mark Lemmon, the MER science team member who is the “brains” behind Opportunity’s and Spirit’s moon shots. NASA / JPL-Caltech / Viking Project

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