NASA discovers phenomenon that could have led to water loss on Mars

UPI

29-05-2025

The surface of Mars as seen by the Pathfinder rover in 1997. Photo courtesy of NASA
May 29 (UPI) -- NASA scientists have discovered evidence that could help answer questions surrounding the history of water loss on Mars.
The new research comes after a decade of exploration by NASA's MAVEN (Mars Atmospheric Volatile Evolution) mission shows evidence of an escape process known as "sputtering," during which atoms are knocked out of the atmosphere by what are known as "charge particles," NASA said in a release.
"It's like doing a cannonball in a pool," Shannon Curry, a principal investigator with the MAVEN mission and a co-author of the research report, said. "The cannonball, in this case, is the heavy ions crashing into the atmosphere really fast and splashing neutral atoms and molecules out."
Scientists have an abundance of evidence that water existed on the Martian surface billions of years ago, but they have been trying to find out where it went. Research has shown that when Mars lost its magnetic field, its surface was exposed to solar wind storms that allowed the liquid water to escape into space.
But that does not explain why the once-thick Martian atmosphere was almost entirely stripped away. Sputtering, the new report says, could help explain it.
"It's like we found the ashes from a campfire," Curry continued. "But we wanted to see the actual fire, in this case sputtering, directly.
The team used a series of MAVEN tools to measure several atmospheric factors in both daylight and dark at low altitudes to observe the phenomenon, which took years to complete.
"The combination of data from these instruments allowed scientists to make a new kind of map of sputtered argon in relation to the solar wind," the NASA release said. "This map revealed the presence of argon at high altitudes in exact locations that the energetic particles crashed into the atmosphere and splashed out argon, showing sputtering in real time."
Researchers determined at least one of the causes for the loss of water on the Martian surface, but they were also able to recreate the conditions that may have made the planet inhabitable billions of years ago.