NASA’s Mars 2020 Perseverance rover has started the Red Planet’s quest for ancient life signatures. With its mechanical arm flexing 7 feet (2 metres), the rover tests the sensitive detectors it carries, obtaining its first scientific readings. Together with the analysis of rocks using X-rays and ultraviolet light, the 6-wheeled scientist will zoom in to shut up small pieces of rock surfaces that could demonstrate historical microbial activity.
Abigail Allwood, PIXL’ s lead researcher at NASA’s Jet Propulsion Laboratory in Southern California, said PIXL, a Planetary Instrument for X-ray Lithochemistry that yielded unexpectedly good scientific results while still being evaluated. At the end of the arm, a small calibration target – intended to test instrument settings – was utilised for lunchbox-size instrument on board Perseverance and the composition of martian dust clinging to the target was determined.
“We have our finest ever Martian dust composition study before even looking at rock,” Allwood said.
This is just a little taste of what PIXL is supposed to demonstrate, paired with the other arms’ instruments, as it zeroes on promising geological features over the weeks and months to come.
Scientists suggest that Jezero Crater had a crater lake thousands of years ago, making it the preferred landing place for Perseverance. The crater has been dried out for a long time and the rover is now crossing its red, shattered floor.
“If life was there in Jezero Crater, there could be evidence for this life,” said Allwood, a prominent member of the “arm science” team in Perseverance.
PIXL’s chemicals maps can be merged with mineral maps created by SHERLOC and its collaborator, WATSON, in order to provide a thorough picture of rock structures, contours and composition. SHERLOC – short for scanning Raman & Luminescence habitat for organics & chemicals – uses a UV laser to identify certain minerals in rock, while WATSON takes close-up images that scientists can use to determine grain size, roundness, and texture, all of which will help to determine the shape of rock.
Early WATSON surveys have already provided an array of Martian rock data, experts have revealed, including a diversity of colours, grain size in the sediment, and even “cement” within grains. Such characteristics can provide vital hints about training history, water movement and old Martian habitats. And, together with PIXL, they can provide Jezero Crater a larger environmental and even historical perspective.
“What is the floor of the crater comprised of? What were the circumstances on the floor of the crater?” asks Luther Beegle of JPL, SHERLOC’s lead investigator. “That tells us a lot about Mars’ early days and even how Mars was formed. If we have an understanding of what Mars history is like, we can grasp how life can be proven.”
