This artist’s concept depicts the early Martian environment (left) – believed to contain liquid water and a thicker atmosphere – versus the cold, dry environment seen at Mars today (right).
NASA’s Mars Atmosphere and Volatile Evolution is in orbit of the Red Planet to study its upper atmosphere, ionosphere and interactions with the sun and solar wind. Scientists will use MAVEN data to determine the role that loss of volatiles from the Mars atmosphere to space has played through time, giving insight into the history of Mars’ atmosphere and climate, liquid water and planetary habitability.

MAVEN is part of NASA’s Mars Scout program, funded by NASA Headquarters and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Launched in November 2013, MAVEN arrived at the Red Planet on Sept. 21, 2014, completing an interplanetary journey of 442 million miles (711 million kilometers).

Credit: NASA’s Goddard Space Flight Center

Additional images:

http://www.nasa.gov/content/goddard/the-look-of-a-young-mars-2/
http://www.nasa.gov/content/goddard/the-look-of-a-young-mars-3/