Today scientists working with NASA's Mars Reconnaissance Orbiter released an awesome color view of Phobos, which at just over 16 miles long is only a little bigger than Manhattan Island.
Still, it's a fascinating place. At the right end of the image here you can see the large crater Stickney and, radiating away from it, a series of surface fractures created during its formation.
Mars-orbiting spacecraft have been photographing Phobos since the early 1970s, and you can find plenty of other snapshots — for example, ones taken by NASA's Mars Global Surveyor, by the European Space Agency's Mars Express, and even by the Soviet Union's ill-fated Phobos spacecraft.
Ah, yes — the Phobos mission. It's been nearly 20 years since the Soviet Union launched a nearly identical pair of spacecraft toward Mars. Phobos 1 was lost a couple of months after launch due to a programming error. Phobos 2 made into Martian orbit, had rendezvoused with the moon, and was days away from dropping two little landers when it fell silent due to computer failure. Boy, that sure brings back (painful) memories!
Remarkably, the Russians are about to try again. Phobos-Grunt, to be launched next year, will attempt to land on the moonlet and return a sample of its surface to Earth. ("Grunt" is Russian for soil or ground.) There's not a lot of information available on the mission yet, but try this summary from the European Space Agency and this one written by the mission's chief scientist.
Back to the picture seen here, it was taken with MRO's main camera, called Hi-RISE, but to call it a "camera" doesn't do it justice. It's really a beefy telescope with a 0.5-meter (20-inch) aperture and f/24 optics. It was designed to resolve details on the Martian surface only 1 foot across, and it's been doing just that since MRO slipped into orbit around Mars two years ago.