A detailed examination of Martian dust devils confirms that winds can blow much stronger than previously thought: in some cases, 158 kilometers per hourThe analysis, based on two decades of observations from orbit, rethinks the behavior of the climate near the surface of Mars.
The research, led by a team from the University of Bern using data from the European Space Agency, shows a more dynamic picture than expected and provides practical information for exploration. According to the authors, plan landings and operations of future modules and rovers on the red planet.
What the new dust devil catalog reveals
The team identified and followed 1.039 dust devils similar to small tornadoes from images from the Mars Express and ExoMars Trace Gas Orbiter (TGO) orbiters. For about 300 of them, they used pairs of stereoscopic images taken seconds apart, which allowed them to measure displacements and deduce the speed and direction of winds near the ground.
The results indicate that, around these eddies, the currents They can reach speeds of up to 158 km/h in various regions of the planet. Until now, surface measurements have typically remained below 50 km/h and only in exceptional situations have they reached around 100 km/h, so the new catalog clearly expands the observed upper limit.
The activity of the dust devils is seasonal and diurnal: They appear mainly in spring and summer of each hemisphere, they last a few minutes and are most frequent between 11:00 a.m. and 14:00 p.m. local time. They were most frequently detected on dusty plains such as Amazonis Planitia, although they were also observed in the rugged terrain of the southern highlands.
How they were measured and what the data tells us
Stereoscopic images, captured from the same point with a slight time lag, allow us to see how the vortex moves between frames and reconstruct its motion. According to specialists like Nicolas Thomas, virtual anemometers capable of mapping the wind at a local scale.
To sift through the vast archive of images from Mars Express and TGO, the team applied automated detection and tracking techniques. This allowed them to estimate, in addition to speed, the prevailing wind direction and its daily variability. Large regions of the northern lowlands, fine powder, concentrate many of these events, although they are not exclusive: they also emerge on rougher terrain in the south.
The fact that the gusts are so intense has direct consequences on the Martian dust cycle and helps explain why is mars redThe authors see it as very likely that these whirlwinds inject particles into the atmosphere, promoting cloud formation, the development of regional storms and even influencing the loss of water vapor into space.
Implications for future missions to Mars
Knowing the wind speed and direction in areas of interest helps plan the arrival and deployment of surface hardware. ExoMars Rosalind Franklin It already contemplates landing windows that avoid the season of large dust storms, a key precaution to minimize risks.
For rovers and modules with solar panels, these data allow estimating how much dust could be deposited and how often self-cleaning would be necessary. They also help predict when the wind itself might be beneficial in clearing the panels or, conversely, when it increases abrasion and buildup.
Unlike Earth, lacks rain that removes suspended dust, so the particles can remain floating for a long time and travel great distances. This behavior underscores the importance of continuous monitoring to protect equipment and prolong its useful life.
The portrait that emerges is of a windier Mars than previously assumed, with eddies capable of reaching peaks of 158 km/h and a notable contribution to the dust cycleWith the support of long-running Mars Express and TGO observations and the advancement of new analytical tools, the Red Planet's lower atmosphere is beginning to reveal patterns that will be crucial for both science and safe exploration.