Phobos Transit Viewed by Opportunity on Sol 3078

Phobos, the larger of Mars' two moons, transits in front of the sun in this sequence of 10 images taken by the panoramic camera (Pancam) of NASA's Mars Exploration Rover Opportunity during the afternoon of the rover's 3,078th Martian day, or sol (Sept. 20, 2012). The apparent speed of the transit is accelerated in this clip.

Image credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.