NASA mission to determine the role that loss of volatiles from Mars’ atmosphere to space has played through time, giving insight into the history of Mars' atmosphere and climate, liquid water, and planetary habitability. It is the first Mars mission managed by the Goddard Space Flight Center.

Launched from Cape Canaveral on 18 November 2013 aboard an Atlas rocket, the craft has eight instrument sensors used to explore the Red Planet’s upper atmosphere, ionosphere, and interactions with the sun and solar wind. MAVEN achieved Mars orbit on 21 September 2014. In June 2017, the spacecraft achieved 1 000 Earth days in orbit exploring the planet’s upper atmosphere. To date it has made several key science findings, including: indications that there are dynamical processes of exchange of gas between the lower and upper atmosphere which are not yet understood; solar wind particles that can penetrate the upper atmosphere deeper than expected; detection of metal ions resulting from incoming particles of interplanetary dust; discovery of new types of aurora unrelated to the planet’s magnetic field; a seasonal variation of hydrogen in the upper atmosphere; and evidence that large amounts of gas have been lost to space through time via the Sun and its solar wind, thereby changing its climate.