New research unveiled on Sunday by NASA could point to the existence of life on the Red Planet, as well as a range of other exciting possibilities.
On Sunday, the space agency generated buzz with a statement about the latest find by its Curiosity rover: rocks that contain organic carbon, which may indicate the existence of ancient bacteria or any other diverse examples of “complex organic molecules formed by life.”
While analyzing rocks and other sediment collected by the rover across the Red Planet, researchers found an ancient carbon cycle that could have a “biological basis” and resembles the types of fossilized remains of microbial life discovered in parts of our own planet that date back some 2.7 billion years.
A tell-tale sign could be found in the two stable isotopes – 12 and 13 – that were found in the Martian carbon.
While the find offers tantalizing hope that life may have existed on Mars, the researchers are holding out hope that they can find other indicators of what caused these carbon signatures.
“On Earth, processes that would produce the carbon signal we’re detecting on Mars are biological,” said Prof. Christopher House at Penn State University, the lead author of the study. “We have to understand whether the same explanation works for Mars, or if there are other explanations, because Mars is very different.”
🧐Curiouser & curiouser! I found samples with unusual carbon isotopes, which are key in understanding the evolution of planets. On Earth, this is linked to life but it may still be created by geology. What does it mean on Mars? Ah, that’s the great puzzle! https://t.co/xLKj8QmEL9 pic.twitter.com/L3Gf8oFctP
— Curiosity Rover (@MarsCuriosity) January 18, 2022
Indeed, a complex range of different factors may make biological processes radically different on Mars than on Earth. The Red Planet, for example, is far smaller, colder, and has weaker gravity as well as different gases in its atmosphere. Likewise, Martian carbon could be circulating in the absence of any life, unlike here on Earth.
“There’s a huge chunk of the carbon cycle on Earth that involves life, and because of life, there is a chunk of the carbon cycle on Earth we can’t understand, because everywhere we look there is life,” noted Curiosity researcher Andrew Steele from the Carnegie Institution for Science in Washington, D.C.
Researchers are looking into the widespread existence of the simple organic molecule methane as a potential telltale sign of microbial life, with the focus of exploration lying near the Gale Crater – a deep lake that is 3.5 billion years old and is said to store complex organic molecules and many of the key ingredients for the existence of ife.
“Defining the carbon cycle on Mars is absolutely key to trying to understand how life could fit into that cycle,” Steele noted. “We have done that really successfully on Earth, but we are just beginning to define that cycle for Mars.”