Clues on the Martian surface, such as features resembling dry riverbeds and minerals that only form in the presence of liquid water, suggest that Mars once had a denser atmosphere, which supported the presence of liquid water on the surface. As part of a dramatic climate change, most of the Martian atmosphere was lost. Maven will make definitive scientific measurements of present-day atmospheric loss that will offer insight into the Red Planet's history.
Approval to proceed with development followed a review at NASA Headquarters of the detailed plans, instrument suite, budget, and risk factor analysis for the spacecraft.
The mission is led by its principal investigator, Bruce Jakosky of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. NASA Goddard Space Flight Center, Greenbelt, Md., manages the mission, with is part of the NASA Mars Exploration Program managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif.
Link to full news release at http://www.nasa.gov/maven .