New images of the surface of Mars have been released by US space agency Nasa, and may help scientists understand how the planet's landscape, once favourable for life, changed into the current uninhabitable conditions. The colour photos, taken by the Mars rover Curiosity last Thursday, show stunning views of finely layered rock formations. The rover has been stationed at the 5,486m Mount Sharp, specifically its Murray Buttes region, since 2014. The National Aeronautics and Space Administration says the rocks are eroded remnants of ancient sandstone that originated when winds deposited sand after lower Mount Sharp formed. "Studying these buttes up close has given us a better understanding of ancient sand dunes that formed and were buried, chemically changed by groundwater, exhumed and eroded to form the landscape that we see today," Sky News quoted Curiosity Project scientist Ashwin Vasavada as saying, describing the landscape as "a bit of American desert south-west on Mars".