NASA/Jim Grossman
MAVEN, which stands for Mars Atmosphere and Volatile Evolution, should arrive at the Red Planet in Sept. 14. Its goal is to measure the composition of Mars' upper atmosphere, giving scientists clues about how the planet lost its atmosphere and surface water over time.
The mission is unique because it is the first Mars explorer to focus exclusively on Mars' upper atmosphere, rather than looking for chemical traces of water on Mars or signs that the planet could have once supported life (currently the objective of the Curiosity rover).
MAVEN will explore "the single biggest unexplored piece of Mars so far," Bruce Jakosky, the mission's principal investigator, said in a statement.
More than four billion years ago, scientists think that Mars has a thick atmosphere and was warm enough to support liquid water. Then, something happened. Mars was stripped of its thick atmosphere, oceans of flowing water disappeared, and Mars became the cold desert that we know today.
Scientists hope MAVEN will help solve the long-standing mystery of how Mars' climate changed so drastically.