MIT Develops New Spectroscopic Technique to Search Life on Mars

Scientists from Massachusetts Institute of Technology have developed a new spectroscopic method to help the new Mars Rover to quickly and non-invasively identify rock and soil samples.

These rocks are relatively unaltered and have maintained much of their original composition, boosting the chances of finding evidence of microbial life on the red planet.

The new technique, described in a paper published in the journal Carbon, is based on an improved way in interpreting the results of Raman spectroscopy; a common, non-destructive process used by geologists to identify the chemical composition of ancient rocks.

Raman spectroscopy is typically used to identify whether a sample contain carbonaceous matter. The presence of carbonaceous matter suggests that the sample may also have harbors sign of life. With the new improve spectroscopy techniques; researchers can now also estimate the ratio of hydrogen to carbon atoms in a sample.

Hydrogen can be used as basis to determine if a certain sample is pristine or not. If the sample has low hydrogen, it is possible that it has experience more heating, altering its organic matter and losing hydrogen in a form of methane.

To test out their new technique, the researchers analyzed samples of sediments whose chemical composition is already known. Furthermore, additional sample of ancient kerogen were used.

Using their improved interpretation of Raman spectroscopy, the researchers were able to get the ratio of hydrogen to carbon closely matched to the original ratio of the samples.

"This may help in deciding what samples the 2020 rover will archive," said Roger Summons, professor of earth, atmospheric, and planetary sciences at MIT, in a statement. "It will be looking for organic matter preserved in sediments, and this will allow a more informed selection of samples for potential return to Earth."

The 2020 Mars Rover would be equipped with wide suites of scientific tools. Among those is the Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHELOC) that will acquire Raman spectra from samples on or below the surface of Mars.