Telephoto Phobos

Image source with larger version
Credit: NASA/JPL-Caltech/University of Arizona

My one complaint is that Mars Reconnaissance Orbiter didn't turn its absurdly powerful camera on one of the Martian moons sooner. Presumably some careful conjunction of orbits was required. See the rest of the images here.

Phobos is an almost microscopic 27 km across at its widest point, and orbits Mars in a mere 8 hours. It hugs so close to the equator of its mother planet, that it can't even be seen from higher Martian latitudes.