Solar eclipses on Mars a Martian day is 24 hours 37 minutes long, meaning that Phobos can create two eclipses per Martian day. These are annular eclipses, because Phobos is not quite large enough or close enough to Mars to create a total solar eclipse. Deimos is too small (about ) and too far from Mars to cause an eclipse. The best an observer on Mars would see is a small spot crossing the Sun's disc. Both moons are too small to cast a shadow on Mars that can be seen from Earth. However, shortly after the first artificial satellites were placed in orbit
Phobos monolith an imaging sub-contractor at NASA Johnson Space Center. Lan Fleming considered the possibility that the Phobos monolith may be artificial and not a geological feature or rock. The general vicinity of the monolith is a proposed landing site by Optech and the Mars Institute, for an unmanned mission to Phobos known as PRIME (Phobos Reconnaissance and International Mars Exploration). The PRIME mission would be composed of an orbiter and lander, and each would carry four instruments designed to study various aspects of Phobos' geology. At present, PRIME has not been funded and does not have a projected launch date. Former