NASA’s Curiosity rover has made a groundbreaking discovery on Mars, revealing the largest organic molecules ever found on the planet. These molecules, known as alkanes, are hydrocarbons composed of carbon and hydrogen atoms, and were discovered in a sample of mudstone from the ‘Cumberland’ rock in the Yellowknife Bay region of Mars’ Gale crater.
While these molecules do not prove ancient life on Mars, they show that the planet’s sediments could have preserved chemical signatures of past life. Scientists say this discovery demonstrates that analyzing Martian samples can reveal clues about potential past habitability.
The largest organic molecule found was dodecane, with 12 carbon atoms and 26 hydrogen atoms. However, researchers believe it is still dwarfed by similar molecules on Earth. The origin of these large alkanes remains unclear, but laboratory experiments suggest they could have come from the breakdown of fatty acids entombed in clay-rich sedimentary materials over 3.7 billion years ago.
The discovery was made possible by Curiosity’s Sample Analysis on Mars (SAM) suite of instruments, which allowed researchers to analyze the sample and identify the elements vital for life, such as carbon, nitrogen, oxygen, phosphorus, and sulfur.
While this finding is significant, it also highlights the limitations of current technology, as Curiosity’s SAM instruments are unable to detect organic molecules larger than dodecane. To further investigate the presence of life on Mars, scientists plan to retrieve samples from the planet and bring them back to Earth for analysis.
Source: https://www.space.com/the-universe/mars/curiosity-mars-rover-discovers-largest-organic-molecules-ever-seen-on-red-planet