NASA’s Curiosity rover has discovered the largest organic compounds ever identified on Mars, a huge step forward in the quest for past life. The discovery, reported in the Proceedings of the National Academy of Sciences, indicates that prebiotic chemistry on Mars may have advanced further than previously thought.
The rover’s Sample Analysis at Mars (SAM) mini-lab detected decane, undecane, and dodecane in a rock sample. These carbon-based compounds, potentially remains of fatty acids, are critical chemical building blocks of life on Earth. Fatty acids are essential for creating cell membranes, although they can also be produced by non-biological chemical reactions.
Curiosity had previously found simple organic molecules, but the newly discovered chemicals are more complicated. Their presence on the Martian surface raises expectations that biosignatures—molecules that indicate life—may yet exist. Scientists believe that Mars’ ancient lake conditions, such as Gale Crater’s Yellowknife Bay, could have supported life-forming processes.
While the actual origin of these molecules is unknown, the discovery supports the case for returning Martian samples to Earth for further research. “We are ready to take the next big step and bring Mars samples home,” stated NASA scientist Daniel Glavin.
