There are some powerful winds on Mars, but just how powerful was only discovered recently. David Choi of NASA's Goddard Space Flight Center used images of dust devils taken by Mars Reconnaissance Orbiter's HiRISE camera to determine the speed of the swirling dust devils.
|Tracks Left by Dust Devils on Mars|
But just how did he do this?
Choi looked at different HiRISE images of the same dust devil and determined how far four distinct cloud features had moved from one photo to the next. Because he knew the time elapsed between each image he was able to calculate how fast the swirling dust devil was moving.
So just how fast was the wind blowing on Mars?
Really fast. In some cases the wind speeds were 45 m/s (162 km/hr), well above 33 m/s (118.8 km/hr) which constitutes hurricane force winds on Earth. The typical wind speed was from 20-30 m/s (72-108 km/hr).
The dust devils observed were anywhere from 30-250 meters in diameters and rose from 150-700 meters into the sky.