Scientists involved in NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission, which is being led by the LASP team at the University of Colorado Boulder, have identified the process that appears to have played a key role in the transition of the Martian climate from an early, warm and wet environment that might have supported surface life to the cold, arid planet Mars is today.
MAVEN data have enabled researchers to determine the rate at which the Martian atmosphere currently is losing gas to space via stripping by the solar wind. The findings reveal that the erosion of Mars’ atmosphere increases significantly during solar storms. The scientific results from the mission appear in the Nov. 5 issues of the journals Science and Geophysical Research Letters.
Two NASA and one European spacecraft, including NASA’s MAVEN mission—led by LASP—have gathered new information about the basic properties of a wayward comet that buzzed by Mars Oct. 19, directly detecting its effects on the Martian atmosphere.
Data from observations carried out by MAVEN, NASA’s Mars Reconnaissance Orbiter (MRO) and the European Space Agency’s Mars Express spacecraft revealed that debris from the comet, known officially as Comet C/2013 A1 Siding Spring, caused an intense meteor shower and added a new layer of ions, or charged particles, to the ionosphere. The ionosphere is an electrically charged region in the atmosphere that reaches from about 75 miles (120 kilometers) to several hundred miles above the Martian surface.
Using the observations, scientists were able to make a direct connection between the input of debris from the meteor shower to the subsequent formation of the transient layer of ions—the first time such an event has been observed on any planet, including Earth, said the MAVEN research team.