Our Universe is vast - the Milky Way alone contains more than 200 billion star systems and various NASA missions have discovered over two thousand exoplanets. With so much to observe and discover, it is easy to lose sight of the possibility of life within our own solar system! Luckily for us, NASA’s Curiosity rover is here to help expand on those possibilities. Recent publications from NASA scientists detail Curiosity’s latest discovery of methane and carbon, also known as the potential building blocks for life. Does this mean Mars is, once again, a candidate for sustaining life?
The Curiosity rover has been roaming the rocks of Mars since its landing in 2012 and over the last six years, it looks as though our patience is finally paying off. This adventurous space-buggy has had one primary mission: to find organic compounds on Mars. Since its landing, Curiosity has periodically tested Mars’ atmosphere for traces of organic compounds. In 2014, scientists were able to compile information to prove that methane is present in the atmosphere. Recent scientific publications provide correlational data suggesting the release of methane into Mars’ atmosphere (or the sudden “spike” of methane) occurs cyclically, much like Earth’s seasons. The majority of methane gas on Earth is generated from living beings; for those hoping life once existed on Mars, cyclical methane spikes are promising. (1)
Last week, Curiosity drilled through Martian rock samples taken from the ancient lake bed of the Gale Crater, and analyzed the samples. The results? The gas output from these rocks contained organic molecules similar to those found in rocks on Earth. Organic molecules are chemical compounds that contain carbon, an essential ingredient for life. On Earth, carbon is present in all life (like you!) and helps make Earth habitable and sustainable. The presence of carbon on Mars is yet another piece of the puzzle that scientists have been trying to solve since the Viking lander missions in the 1970s. (2)
The hunt for life on Mars is not new. Research into the possibility of life on Mars began decades ago, but sadly, chlorine in the Martian soil contaminated samples, rendering the data unusable. Last week’s information gives us new insight into Mars’ mysterious past, and while this new analysis is not a definitive indication that life on Mars exists, it certainly entertains the possibility that Mars was once habitable. Curiosity’s discovery of organic compounds may very well provide the next step towards deciphering evidence of organismal life. Additional missions are planned; in 2020, a new Mars rover, the ExoMars, will land on the Red Planet. The ExoMars will be able to drill even deeper into the soil to sample and test pristine Martial soil - soil that has not been exposed to solar radiation or dust storms. (3) With ever increasing research and space exploration, our quest and hope to find life beyond Earth is by no means over - it is just beginning.