Scientists are perplexed by the discovery of what looks like footprints on the surface of Mars.
Images captured by the Curiosity Rover show an unusual feature on the Red Planet’s surface – broad, shallow pits unlike anything researchers have previously spotted.
The discovery was made as Curiosity explored Mount Sharp, a vast mountain rising from the floor of Gale Crater.
The rover has been exploring Mars since landing in 2012, and despite more than a decade on the planet, it continues to find things that puzzle scientists back on Earth.
Small pits and depressions are relatively common on Mars. They can form when harder nodules or pebbles embedded in rock gradually weather away, leaving a hollow behind.
But the newly observed features are different. They are much wider and shallower than similar pits seen previously, and researchers could not identify obvious objects that might once have occupied them.
The Curiosity team used the rover’s cameras and instruments to examine the features in detail. MAHLI and the Mastcam instrument captured overlapping images that can be combined to produce three-dimensional models of the pits and their structure.
The team does not believe the marks are actual footprints, but the unusual formations provide a new clue about the geological processes that have shaped this part of Mount Sharp.
The surrounding bedrock also provided plenty for Curiosity’s instruments to investigate. Mastcam images and measurements from the ChemCam instrument revealed layers whose texture and structure changed over relatively short distances.
Scientists say these variations could indicate changes in the conditions under which the sediments were deposited.
The rover also examined rough, grey layers that were more resistant to erosion than the surrounding rock. ChemCam, MAHLI and the Alpha Particle X-ray Spectrometer (APXS) analysed the material, which may have a different chemical composition from the bedrock around it.
Follow Metro on WhatsApp to be the first to get all the latest news
Metro’s on Whatsapp! Join our community for breaking news and juicy stories.
After almost 14 years on Mars, Curiosity continues to provide scientists with new glimpses of the planet’s geological history – and, occasionally, features they have never seen before.
In an image taken in 2013, UFO hunters thought they’d spotted a wrinkly mushroom on the planet’s surface.
MORE: Nasa finds ‘once-in-a-lifetime’ moon crater bigger than the Roman Colosseum
MORE: Scientists find 27 strange new objects hovering on the edge of our Solar System
MORE: ‘Human kneecap’ washed up on beach was just a sea potato