The images of tracks left behind by Curiosity and the Perseverance rover on Mars are reminders of human ingenuity on another planet that has remained untouched for millenniums. However, the two rovers are not the only things leaving their marks on this uninhabitable world, there are natural forces at work as well.
Scientists at the Physical Research Laboratory in Ahmedabad have spotted thousands of tracks on the surface created by tumbling boulders. These boulder tracks can be used to pinpoint recent seismic activity on the planet as humans become more and more interested in the Red Planet with plans to develop colonies in the near future.
“Mars is currently active,” says Dr S Vijayan, Assistant Professor with the Planetary Science Division at the Physical Research Laboratory, who led the research.
MOVEMENT ON MARS
The study published last month in Geophysical Research Letters states that it takes about two to four Martian years (four to eight Earth years) for these boulder tracks to disappear, whereas on Earth they are rarely preserved. These ejections and tracks can be used to recognise very recent surface processes on planetary surfaces.
When a boulder falls, at each bounce the regolith (Martian surface material) on the surface is thrown out in a unique pattern. On Mars, these patterns appear V-shaped, with the spread pointing downslope and the spacing between each bounce is non-uniform. The spatial spread of BFE varies from bounce-to-bounce and boulder-to-boulder.
