The High Martian Wind

(In all caps because that’s a title, isn’t it?) Science News reports on the work the MAVEN probe is doing mapping the movements of the upper atmosphere of Mars:

“Looking at how gas circulates in that layer allows us to better understand the rate at which the atmosphere is being lost and the way it’s being lost,” says study author Mehdi Benna, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md.

Wind movement in Mars’ thermosphere is much simpler than on Earth, data from the orbiter show. A single circulating flow persists from season to season, continually moving air from the planet’s dayside to its nightside, whereas on Earth there are multiple flow patterns at any one time. “Oceans on Earth complicate the circulation patterns,” Benna says. “Mars doesn’t have all that.”

The spacecraft, which arrived at Mars in 2014, also recorded waves in the thermosphere generated by winds near the ground diverting around mountains and canyons. “When the spacecraft is flying over a mountain, we can see the wind shifting to accommodate the presence of that mountain 200 kilometers below,” Benna says. “MAVEN doesn’t carry [traditional] cameras … but we can see a picture of the topography in the winds.”