Scientists have recently found the clearest sign of life on Mars. Back in July the newest Mars rover, Perseverance, used its core driller to take a sample from a rock formation called “Chevaya Falls.” Scientists found something astonishing: small circular patterns called a “Leopard Spots.” Because such spots are found on Earth in microbe rich environments, the find suggests ancient microbial life.
Perseverance used its onboard SHERLOC and PIXL instruments to find that the spots also contained minerals like Vivianite and Greigite, which form on Earth in biological processes. Greigite is thought to be one of the main components for life and is essential in microbial metabolic processes. Vivianite results from decomposed living things like fossils. The pattern on the leopard spot is seen on Earth in biologically-live soil. It also appears in a fundamental metabolic process called extracellular electron transfer. These elements make the leopard spot the most plausible case of alien life yet.
On Earth, NASA scientists remain cautious. Until a sealed sample is analyzed on Earth, scientists won’t be able to any conclusions.
Some scientists think that the leopard spot was formed from nonbiological processes. The main reason is that if the leopard spot really was organic, it would be less likely that the organic matter could last so long without disintegrating in Mars’s harsh climate. Therefore, nonbiological process is more plausible because it would be more durable in Mars’s climate.
For now, scientists at NASA are going to classify this discovery as a “Potential Biosignature,” due to the fact that the sample ranks low on the confidence of life detection scale (CoLD scale).
Other scientists are still optimistic about the discovery, “After a year of review, they have come back and said, we can’t find another explanation,” said acting director Sean Duffy. “This very well could be the clearest sign of life.”
Only continued scientific research and lab tests will help confirm if the spots were a fluke or a true sign of life. Right now though, the spots are the farthest we’ve come in seeing if there is alien life or not.
If NASA does confirm this discovery that Mars once supported microbial life, scientists’s entire perspective of Mars would be upturned. It would extend the timeline of habitability on Mars much farther back than thought before. The findings could also help in finding ancient water sources and microbial ecosystems that Mars could have sustained.
Perseverance has already sealed the samples in capsules waiting to be returned back to Earth. It’s unclear if NASA’s mission to return the capsules to Earth will be put into effect as a proposal threatens to slash NASA’s budget by half.
Either way, the Perseverance Rover will continue to explore for more clues, while scientists on Earth figure out if the breakthrough discovery was truly a sign of alien life.