NASA’s Perseverance rover is looking for signs of ancient life on Mars and has now collected some of the most promising samples yet.
Several rock samples containing organic matter were discovered in Jezero Crater, a 28-mile-wide crater that scientists believe once housed a river delta that formed about 3.5 billion years ago.
“Jezero was chosen for this mission because… it allows us to explore an ancient habitable environment (and) seek evidence of possible, Martin life in rocks deposited at that time, about 3 and a half billion years ago,” Perseverance project scientist Ken Farley said in a recorded panel about the rover’s findings.
“I want to emphasise that this mission is not looking for extant life, or things that are alive right now. Instead, we’re peering into the distant past, when Mars’ climate was very different from what it is now “Farley continued.
Perseverance launched in July 2020 and landed in Jezero Crater in February 2021. According to NASA, the rover has collected four samples from the delta since July 7 of this year, bringing the total number of collected “scientifically compelling rock samples” to 12.
Organic matter found in Martian rocks
Perseverance is currently researching the sedimentary rocks of the delta. The rover previously explored the floor of Jezero Crater, discovering igneous rocks. Farley said in a news release that the contrast between the two “provides us with a rich understanding of the geologic history after the crater formed as well as a diverse sample suite.”
The project scientist, for example, pointed to one collected mudstone that contains “interesting organic compounds.”
Organic molecules were discovered in “Wildcat Ridge,” a 3-foot-wide rock thought to have formed billions of years ago with mud and fine sand in an evaporating saltwater lake, using an instrument called Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals, or SHERLOC.
“We’re clearly uncovering a larger story than what’s going on in Jezero Crater. We found signals that we believe are from organic matter on every target we’ve observed with SHERLOC so far “SHERLOC scientist Sunanda Sharma spoke on the panel.
Sharma went on to say that this was not “unexpected,” as it was consistent with previous research. “However, it does state that organics appear to persist in the extremely harsh Martian surface environment, which is extremely exciting for us.”
According to NASA, the Curiosity Mars rover discovered organic matter in rock-powder samples in 2013. Perseverance has previously detected organics in Jezero Crater, but the latest discovery was made in an area with conditions that would have allowed life to exist in the distant past, according to scientists.
“It’s significant that the organic matter was discovered in a sedimentary rock, which is known for preserving fossils of ancient life on Earth,” Farley said.
“However, as capable as our instruments on Perseverance are, further conclusions about what’s in the Wildcat Ridge sample will have to wait until it’s returned to Earth for in-depth study as part of (NASA and ESA’s) Mars Sample Return campaign.”