NASA | Searching for Mars’ Missing Atmosphere
Early in its lifetime Mars probably had a thicker atmosphere, possibly with clouds in the sky, and flowing water on its surface. The atmosphere on Mars today is only one percent as thick as Earth’s, leaving the planet dry and dusty. Scheduled for launch in November, MAVEN will use its Neutral Gas and Ion Mass Spectrometer to study the interaction of neutral gases and ions in the Martian atmosphere with the solar wind. MAVEN will be the first mission to focus on Mars’ upper atmosphere and will investigate how the atmosphere has thinned and how Mars’ climate has evolved, helping scientists to understand how Mars lost its atmosphere over time.