For the first time, researchers have observed a key driver of Mars’ atmosphere erosion, shedding light on the planet’s mysterious past. After over nine years of analyzing satellite data from NASA’s MAVEN spacecraft, a team led by planetary scientist Shannon Curry has detected unmistakable signs of atmospheric sputtering.
Sputtering occurs when ions are accelerated by the solar wind into Mars’ atmosphere, causing energy to be transferred and kicking up neutral atoms and molecules. This process can lead to atmospheric loss, including the escape of water vapor from the planet. The team found that argon densities in the upper atmosphere vary depending on the orientation of the solar wind electric field, indicating active sputtering.
The results are significant because they suggest that sputtering is over four times higher than previously predicted and can substantially increase atmospheric loss during solar storms. This supports the idea that sputtering was a crucial mechanism for Mars’ atmospheric escape in the early Solar System.
The findings provide substantial evidence for sputtering’s role in Mars’ atmosphere loss and have implications for understanding the planet’s habitability over time. The discovery is published in Science Advances and marks an important step forward in our understanding of Mars’ mysterious past.
Source: https://www.sciencealert.com/scientists-have-clear-evidence-of-martian-atmosphere-sputtering