NASA’s Curiosity rover has made a significant discovery that could shed light on the possibility of life on Mars billions of years ago. The rover detected long-chain organic molecules, specifically fatty acids, in a 2013 sample drilled from a lake that dried up over 3 billion years ago.
The findings, published in the Proceedings of the National Academy of Sciences, suggest that these molecules could be a chemical relic of ancient life on Mars. However, it’s essential to note that these molecules could also have formed without life. The discovery is considered exciting because it provides further evidence for Curiosity’s successor, Perseverance, which will collect samples for analysis on Earth.
The rover has traveled over 21 kilometers in Gale crater and has spotted other potential signs of life, including goopy organic macromolecules that resemble kerogen and an enrichment in a “light” carbon isotope. The latest result comes from a mudstone sample called Cumberland, which the rover drilled into in 2013.
Researchers have reanalyzed the data using a twin instrument on Earth to help identify the molecules. They found three varieties of alkanes – decane, undecane, and dodecane – which are organic molecules that string together carbon and hydrogen in a line. The team suspects that these molecules could be carboxylic acids or fatty acids, which are common building blocks of cell membranes on Earth.
However, the origin of these molecules is still unclear. Some researchers believe they could have come from chemical reactions in the early Solar System or evolved on Mars from kerogen-like particles. To confirm the findings, scientists will analyze more samples collected by Curiosity and consider using its onboard lab to detect a wider range of alkanes.
This discovery marks an exciting milestone for the ongoing search for life beyond Earth and highlights the importance of continued exploration of the Martian surface.
Source: https://www.science.org/content/article/curiosity-rover-detects-long-chain-carbon-molecules-mars