Moons of Mars 0.07. If viewed from Mars's surface near its equator, full Phobos looks about one third as big as a full moon on Earth. It has an angular diameter of between 8' (rising) and 12' (overhead). Due to its close orbit, it would look smaller when the observer is further away from the Martian equator, and is below the horizon and thus invisible when viewed from Mars's polar ice caps. Deimos looks more like a bright star or planet for an observer on Mars, only slightly bigger than Venus looks from Earth; it has an angular diameter of about 2'. The
Mars Exploration Program used toward a mission that is part of the Mars Sample Return program. As a result of the smaller budget for the MEP, NASA was forced to cancel the Mars Science Orbiter planned for 2016 that would have studied the climate of the planet. NASA does not have any missions for the future of the MEP, as a plan is still being developed that will encompass the next few decades. Mars Exploration Program The Mars Exploration Program (MEP) is a long-term effort to explore the planet Mars, funded and led by NASA. Formed in 1993, MEP has made use of