Perseverance rover unearths a variety of organic molecules in Mars' Jezero Crater

According to astrobiologists, this intriguing clue is significant because on Earth, carbon is commonly linked to biological processes. Nevertheless, on Mars, various non-biological processes could have also generated carbon signatures. Despite this, the potential for life on Mars has not been disregarded.

One thing I’m #SamplingMars for is organic molecules, the “building blocks” of life. The rock I got these two samples from has signals suggesting they may be present. Signs of biology, or another process, maybe? Hear why scientists would love to study sample #6 or #7 up close: pic.twitter.com/cQheyDqybd

— NASA's Perseverance Mars Rover (@NASAPersevere) July 12, 2023

Results revealed the existence of organic compounds in all 10 targets

Scientists surmise that a river originally flowed through the Jezero Crater billions of years ago. And scientific studies indicate that there is a possibility of discovering signs of past habitability in this ancient lake basin. 

The rover drilled into two rock formations within the crater for this study: Máaz and Sétah.

The Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument onboard Perseverance examined the samples. This instrument's expertise lies in the detection of organic chemicals on the Martian surface. 

Notably, the findings unveiled the presence of organic compounds in all 10 selected locations within the Máaz and Sétah rock formations. These compounds are believed to have persisted for a minimum of 2.3 billion to 2.6 billion years.

The results "point to the possibility that building blocks of life could have been present for a long time on the surface of Mars, in more than one place," lead author Sunanda Sharma, a planetary scientist at the California Institute of Technology in Pasadena, told space.com.

They add that these organic molecules seem to be associated with minerals linked to water.

An abundance of organic molecules 

Further investigation uncovered evidence of diverse kinds of organic compounds in various analyzed rocks. This means that the molecules most likely formed through different mechanisms. 

Over the course of billions of years, there might have been a variety of non-biological activities that sparked a cascade of reactions that resulted in the synthesis of organic molecules such as carbon. Or, in one rare possibility, ancient microbes could also have contributed to the formation of organic molecules. 

The researchers emphasized that they were unable to detect specific organic molecules, which would require physical rock samples to be tested in a laboratory setting.

The study also suggests that organic matter may be prevalent on Mars. Earlier, the Curiosity rover found the presence of carbon molecules in rock samples collected from the Gale Crater on Mars.

The results have been published in the journal Nature.

Study Abstract:

The presence and distribution of preserved organic matter on the surface of Mars can provide key information about the Martian carbon cycle and the potential of the planet to host life throughout its history. Several types of organic molecules have been previously detected in Martian meteorites and at Gale crater, Mars. Evaluating the diversity and detectability of organic matter elsewhere on Mars is important for understanding the extent and diversity of Martian surface processes and the potential availability of carbon sources. Here we report the detection of Raman and fluorescence spectra consistent with several species of aromatic organic molecules in the Máaz and Séítah formations within the Crater Floor sequences of Jezero crater, Mars. We report specific fluorescence-mineral associations consistent with many classes of organic molecules occurring in different spatial patterns within these compositionally distinct formations, potentially indicating different fates of carbon across environments. Our findings suggest there may be a diversity of aromatic molecules prevalent on the Martian surface, and these materials persist despite exposure to surface conditions. These potential organic molecules are largely found within minerals linked to aqueous processes, indicating that these processes may have had a key role in organic synthesis, transport or preservation.