As per a team of researchers, most of the water from the atmosphere on Mars was likely stripped away by solar winds, making it the cold, red planet what it is today.
NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission has identified the process that appears to have played a key role in the transition of an early, warm and wet Martian environment that might have supported surface life.
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.
Mars appears to have had a thick atmosphere warm enough to support liquid water which is a key ingredient and medium for life as we currently know it, said astronaut John Grunsfeld.
He added “Understanding what happened to the Mars atmosphere will inform our knowledge of the dynamics and evolution of any planetary atmosphere. Learning what can cause changes to a planet’s environment from one that could host microbes at the surface to one that doesn’t is important to know, and is a key question that is being addressed in NASA’s journey to Mars.”
MAVEN measurements indicate that the solar wind strips away gas at a rate of about 100 grams (equivalent to roughly 1/4 pound) every second.
In addition, a series of dramatic solar storms hit Mars’ atmosphere in March 2015, and MAVEN found that the loss was accelerated. The combination of greater loss rates and increased solar storms in the past suggests that loss of atmosphere to space was likely a major process in changing the Martian climate.
MAVEN has been operating at Mars for just over a year and will complete its primary science mission on Nov. 16.
The study appears in the journals Science and Geophysical Research Letters.