Three new studies have been published on Mars' terrain in the journals Science and Science Advances.
Researchers from Purdue University have analyzed data from NASA's Perseverance Mars rover, which discovered grains of olivine on Mars' surface, adding some green to the endless red Martian landscape. Known as the Red Planet, scientists expected to find minerals and materials of a similar shade when Perseverance first landed on Mars. However, the rover found something unexpected after landing in the Jezero Crater, which once held a large lake when Mars had liquid water, air, and a magnetic field.
Scientists expected to find sedimentary rocks inside the crater, but instead found many volcanic rocks. Much of the rocks are composed of large grains of olivine, one of Earth's most abundant minerals, which makes up more than half of the upper mantle, and is known for tinting numerous Hawaiian beaches green. The Perseverance rover is examining samples up to nearly 4 billion years old, which have remained almost pristine.
On Earth, rocks that age have been mostly destroyed or worn by tectonic plate activity and billions of years of weathering from water, wind, and organic life. Scientists seek to understand how the rocks formed on Mars to inform their understanding of the early conditions on the planet and how they may have supported life to guide the rover as it continues its search for signs of potential life.
"The rocks Perseverance is roving over in Jezero have more or less just been sitting at the surface for billions of years, waiting for us to come look at them. That's one of the reasons that Mars is an important laboratory for understanding the early solar system," said Briony Horgan, a Purdue University associate professor of planetary sciences.
"We're excited to see even better results about organics and ancient habitable environments. I think it's really setting the stage that Mars is this watery, habitable place, and all the samples we're getting back are going to help us understand the history of ancient microbial life on Mars," Horgan said.