Curiosity rover finds evidence that water once existed on the surface of Mars

By Georgina Torbet Published April 2, 2021

NASA’s Curiosity Mars rover took this selfie on May 12, 2019 (the 2,405th Martian day, or sol, of the mission). NASA/JPL-Caltech/MSSS

NASA’s Curiosity rover has found the highest amounts of clay in any sample taken so far during its mission to Mars. To celebrate, the rover snapped a selfie as it explored the aptly-named “clay-bearing unit” where the newest samples were taken.

To generate this selfie, 57 different images captured by Curiosity’s Mars Hand Lens Imager (MAHLI) were combined into one panoramic image. The MAHLI is a camera placed on the end of the rover’s robotic arm, and the arm itself was digitally removed from the final image to show the rover in all its Martian glory.

Recommended Videos

If you look to the left and below the rover in the image, you can see two small drill holes. These two targets are called “Aberlady” and “Kilmarie” and were recently made by Curiosity as it dug through the surface to collect samples. They are the 20th and 21st drill sites for Curiosity on its mission so far.

Curiosity is traveling through the clay-bearing unit as it slowly wends its way up Mount Sharp. This region is of particular interest as clay often forms when water is present, and it is believed that there was water on the surface of Mars billions of years ago. Examining the clay that still exists on the surface could give an indication of whether there were conditions that could have supported life at one point in Mars’ history.

To analyze the samples, Curiosity uses its CheMin instrument (a portmanteau of chemical and mineralogy) which can identify and measure the amount of certain minerals in the Martian rock. Notably, in addition to the clay, the CheMin instrument detected very low levels of hematite in the clay-bearing unit. Hematite was abundant in the nearby Vera Rubin Ridge, where Curiosity was exploring at the start of the year.

These new findings provide compelling evidence there was once water in the region, but researchers still have questions about how water interacted with the rocks. It could be that rocks were formed when water pooled into lakes, with layers of sediment at the bottom. Over time, the sediment formed into the rocks which still litter the surface of the region today.

Topics

Georgina Torbet

Space Writer

Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…

Space

Curiosity captures shimmering, iridescent ‘mother of pearl’ clouds on Mars

NASA’s Curiosity Mars rover captured these clouds just after sunset on March 19, 2021, the 3,063rd Martian day, or sol, of the rover’s mission. The image is made up of 21 individual images stitched together and color corrected so that the scene appears as it would to the human eye.

NASA’s Curiosity Mars rover captured these clouds just after sunset on March 19, 2021, the 3,063rd Martian day, or sol, of the rover’s mission. The image is made up of 21 individual images stitched together and color corrected so that the scene appears as it would to the human eye. NASA/JPL-Caltech/MSSS

Mars has a super-thin atmosphere compared to Earth, with just 1% of its density. And it's very dry there as well, with little or no liquid water on its surface. Both of these factors mean that clouds are a rarity in the martian sky, and they typically only form around the equator during the depths of the Martian winter.

News

NASA orbiter photo shows Curiosity rover on desolate Mars surface

While it’s little surprise that NASA’s newest Mars rover, Perseverance, gets most of the attention these days, we shouldn’t forget that Curiosity, its other rover that arrived on the red planet in 2012, is still busy exploring the Martian surface.

Keen to remind us of the fact, the space agency recently posted a dramatic image of car-sized Curiosity captured by the Mars Reconnaissance Orbiter as it passed overhead at an altitude of around 180 miles.

Space

Detecting organic salts on Mars is key to finding evidence of life there

This look back at a dune that NASA's Curiosity Mars rover drove across was taken by the rover's Mast Camera (Mastcam) on Feb. 9, 2014, or the 538th Martian day, or sol, of Curiosity's mission.

This look back at a dune that NASA's Curiosity Mars rover drove across was taken by the rover's Mast Camera (Mastcam) on Feb. 9, 2014, or the 538th Martian day, or sol, of Curiosity's mission. NASA/JPL-Caltech/MSSS

NASA's Perseverance rover is currently exploring Mars and looking for evidence of the most tantalizing of propositions: That there could once have been life on the red planet. But it's not as simple a flipping open a tricorder to scan for life signs. Detecting whether there ever was life there is a matter of careful, painstaking research.