NASA’s Perseverance rover has found an organic molecules in a Martian crater, but their source remains unclear so far.

The organics – a class of carbon-based molecules – were discovered in Mars’s Jezero Crater and may have a geological source, but could also have been left by ancient microbial life.

The discovery was made using the SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals) instrument on Perseverance’s arm.

These organic compounds mostly appeared connected to minerals linked to water.

This discovery could be a key piece in the puzzle as to whether life exists – or ever did exist – elsewhere in the Solar System beyond Earth.

Organic compounds are molecules composed of carbon and often include other elements such as hydrogen, oxygen, nitrogen, phosphorus and sulfur. Previously, scientists had detected several types of organic molecules of Martian origin — in meteorites blasted off Mars by cosmic impacts that landed on Earth, and in Gale Crater on the Red Planet, which NASA’s Curiosity rover has been exploring since 2012.

As Mars is known to have once been a warmer, wetter world than what we see today, it is an important body for study in the search for habitability.

According to Sunanda Sharma, a planetary scientist at the California Institute of Technology in Pasadena, they are an exciting clue for astrobiologists since they are often thought of as building blocks of life’.

Sharma and her colleagues analyzed data from Perseverance. In February 2021, the rover landed within Jezero Crater, the site of an ancient lake basin that prior work suggested displayed high potential for past habitability.

The crater floor also possesses clays and other minerals that may preserve organic materials.