Phobos, Mars' closest satellite, is named after the Greek word
meaning 'fear', whilst Deimos means 'terror', both following on from the
Mars/War theme. Orbiting at a meagre 6000km from the surface of Mars,
Phobos is the closest moon to its parent planet in the Solar System
(at least that we know of), whilst Deimos is the smallest known planetary moon in the Solar System.
Phobos and Deimos are both believed to be captured asteroids, due to
their irregular shape and small size (Phobos having a 22.2km wide
diameter, whilst Deimos is only 12.6km wide!). Both moons are
heavily cratered and are believed to be made up of rock and ice. Like
our moon they have a coating of dust on their surfaces. Phobos' orbit
is such that it rises in the west and sets in the east, often more than
once in one day.
However, I'm afraid there doesn't really appear to be much of a future left for Phobos as an
independant moon of Mars. This is because in little over 50 million
years it is destined to crash into Mars (with a thud) due to the
planet's tidal forces lowering its orbit (presently at about
1.8cm/year). Nevertheless, it (and Deimos) have been seen by many
spacecraft since it was discovered by Asaph Hall in 1877, such as the
Mariner 9, Viking 1, Phobos and Phobos 2, the last of which even
detected an outgassing coming from Phobos.