 The human exploration of Phobos could serve as a catalyst for the human exploration of Mars and be scientifically valuable in its own right.Most recently, it was proposed that the sands of Phobos could serve as a valuable material for aerobraking in the colonization of Mars.Because of the small delta-v budget of Phobos, a small amount of chemical fuel brought from Earth could be used to lift a very large amount of sand from the surface of Phobos, from a permanent outpost to a transfer orbit.