There are many obstacles for a little rover exploring Mars to deal with, from steep hills to deep ravines to dust which can obscure solar panels or get into mechanical components. Now, the Curiosity rover has one more challenge to add to that list: The densest region of sharp rocks that the rover’s NASA drivers have ever seen.
The rocks, sharpened into vicious points by the Martian wind, were spotted blocking Curiosity’s path in an area called the Greenheugh Pediment on March 18. The team decided they couldn’t risk running Curiosity’s wheels over the jagged rocks, especially since similar rocks had already damaged the wheels earlier in the mission in 2017. “It was obvious from Curiosity’s photos that this would not be good for our wheels,” said Megan Lin, Curiosity Project Manager at NASA’s Jet Propulsion Laboratory, in a statement. “It would be slow going, and we wouldn’t have been able to implement rover-driving best practices.”
Technically called ventifacts, these rocks are formed of sandstone and were nicknamed “gator-back” by the team for the scale-like appearance of the terrain. After Curiosity’s previous run-in with this terrain, the team adapted its driving approach to slow down wear to the wheels, but with this dense field of ventifacts, it was judged best to go around rather than over.
Curiosity has been exploring the Greenheugh Pediment, which is a gently sloped region at the base of Mount Sharp, but now it will head back down toward a region it previously passed through where there are plentiful clay deposits. Clays are of particular interest because they form in water, so studying them can show where water once flowed on Mars’s surface.
“It was really cool to see rocks that preserved a time when lakes were drying up and being replaced by streams and dry sand dunes,” said Abigail Fraeman, Curiosity’s deputy project scientist at JPL. “I’m really curious to see what we find as we continue to climb on this alternate route.”