Martians Moons Jockey for Position

Mars has two moons, named Phobos and Deimos. Phobos is a lumpy potato about 27 km (17 miles) long, and Deimos is more of a charcoal briquette 12.6 km (8 miles) across. Both orbit Mars very close to directly above its equator, so, as seen from the surface, Phobos (which is closer to Mars) will sometimes pass directly in front of Deimos. This is called a mutual event (a kind of eclipse), and if you happen to have a nuclear-powered laser-eyed mobile chemistry lab on the surface you can point the ca...