NASA Perseverance Rover Will Use X-Rays To Look For Alien Life On Mars

NASA's Mars 2020 Perseverance rover has taken off for its ultimate destination on the red planet.

Due to land on the surface of Mars in February next year, there is an intriguing mission goal that the rover has to achieve. It has to look for signs of life on the planet.

NASA Perseverance Rover (Artistic design: NASA)

To fulfill this mission, the Perseverance Mars rover is equipped with a special instrument - PIXL. Short for Planetary Instrument for X-ray Lithochemistry, PIXL is a precision X-ray device powered by artificial intelligence (AI) that will hunt for traces of microscopic life from billions of years ago on Mars.

The lunchbox-size equipment is located on the end of Perseverance's 7-foot-long robotic arm. The purpose of PIXL is to analyse rocks on the surface of Mars for different chemical compositions. It will do so by shooting finely-focused X-ray beams on the rocks around it. This is also a major way in which PIXL differs from its ancestral missions with similar X-ray equipment.

"PIXL's X-ray beam is so narrow that it can pinpoint features as small as a grain of salt. That allows us to very accurately tie chemicals we detect to specific textures in a rock," said Abigail Allwood, PIXL's principal investigator at NASA's Jet Propulsion Laboratory in Southern California.

Well equipped for the job at hand

NASA has specified almost every detail in which it plans to use the rover on the surface of Mars. In essence, it wants the rover to run preliminary tests on rock samples on its own. The samples found to be interesting enough for further analysis, will be stashed in metal tubes and left on the Mars surface for return to Earth by a future mission.

PIXL will play an important role in analysing these samples. Identifying rock textures with maximum precision, PIXL will possibly help discover signs of ancient life, like that in stromatolites - made from ancient layers of bacteria hinting at fossilized ancient life.

NASA's Perseverance Mars Rover (Image: NASA)

NASA mentions that PIXL will also need a hexapod - ¡°a device featuring six mechanical legs¡±, connecting PIXL to the robotic arm. The hexapod will be operated by artificial intelligence to get the most accurate aim.

Once the rover's arm is placed close to an interesting rock, PIXL will use a camera and laser to calculate its distance. Then the legs on the hexapod will ¡°make tiny movements¡± (around 100 microns) to scan the target and map the chemicals found within a postage stamp-size area of it.

"The hexapod figures out on its own how to point and extend its legs even closer to a rock target," Allwood said. "It's kind of like a little robot who has made itself at home on the end of the rover's arm."

The whole process takes eight to nine hours. Since the extreme heat on the red planet will affect the robotic arm, expanding and contracting it, NASA says that the PIXL will have to operate at night for minimal calculation errors.