http://photojournal.jpl.nasa.gov/catalog/PIA17352

This movie clip shows Phobos, the larger of the two moons of Mars, passing in front of the other Martian moon, Deimos, on Aug. 1, from the perspective of NASA's Mars rover Curiosity. The clip includes interpolated frames smoothing out the motion between frames from Curiosity's Mast Camera (Mastcam). Mastcam took images 1.4 seconds apart. With the interpolated frames, this clip has 10 frames per second. It runs for 20 seconds, matching the actual time elapsed.

Curiosity's observations of Phobos and Deimos help researchers make knowledge of the moons' orbits even more precise.

Malin Space Science Systems, San Diego, built and operates Mastcam. NASA's Jet Propulsion Laboratory manages the Mars Science Laboratory mission and the mission's Curiosity rover for NASA's Science Mission Directorate in Washington. The rover was designed, developed and assembled at JPL, a division of the California Institute of Technology in Pasadena.