A broad pit that looks almost like a "footprint" on Mars is unlike anything researchers have ever seen on the Red Planet. (Image credit: NASA/JPL-Caltech/MSSS)Is that a footprint on Mars? Sorry to burst your bubble, but no. However, scientists have found a strange feature unlike anything they've seen before on the Red Planet's surface. What is it?While NASA's Perseverance rover is the newest addition to the agency's robotic Red Planet fleet, its cousin Curiosity is still going strong and finding strange and unusual things on Mars 14 years after landing. In new observations captured on Mars' Mount Sharp, the Curiosity team has identified "features unlike quite anything we have seen in the past," Michelle Minitti, deputy principal investigator for Curiosity's Mars Hand Lens Imager (MAHLI), said in a statement.These mysterious features are a bunch of broad, shallow pits scattered across the Martian bedrock. Why is it incredible?While little pits and divots are common to find on the Martian surface, these wide, shallow pits that researchers saw with Curiosity are quite different from surface features that have been seen before."The pits of this week were much broader and shallower than past features and were not accompanied by obvious objects that were once in the pits," Minitti said. The team collected as much data as they could on the strange pits using Curiosity's various instruments, including MAHLI, the Mastcam camera, ChemCam (the Chemistry and Camera complex) and APX (Alpha Particle X-Ray Spectrometer).They have so far found interesting layers in the pit material that seems chemically different from the main bedrock. But we will have to wait and see what else researchers might be able to learn about these odd pits. How did they form? How long have they existed? What can they tell us about the history of Mars?