Mars Science Laboratory Mars Science Laboratory Mars Science Laboratory (MSL) is a robotic space probe mission to Mars launched by NASA on November 26, 2011, which successfully landed "Curiosity", a Mars rover, in Gale Crater on August 6, 2012. The overall objectives include investigating Mars' habitability, studying its climate and geology, and collecting data for a manned mission to Mars. The rover carries a variety of scientific instruments designed by an international team. MSL successfully carried out the most accurate Martian landing of any known spacecraft, hitting a small target landing ellipse of only , in the Aeolis Palus region of Gale Crater.
Crewed Mars rover rovers, because they need to know at least roughly where they are and where they are going to get to a destination. Dead reckoning was the method used by the Mars Pathfinder rover "Sojourner" for navigation. A GPS satellite network for Mars would mean a constellation of satellites in Mars orbit, but one alternative would be a surface based pseudo-satellites array. These devices would have to be emplaced with high precision, unless they were self-calibrating. An example of criteria for humaned Mars surface rover was expressed by NASA in the surface variant of the aforementioned SEV, in development in during