Mars is the distant, red planet that everyone hopes that will randomly birth two-headed, friendly aliens at one point, and more and more discoveries are increasing the expectations of ancient life on it.

Organic compounds called thiophenes were discovered by NASA’s Curiosity Mars rover, and researchers think their presence is consistent with the possibility of early life on Mars. Thiophenes are found on Earth in coal, crude oil, and interestingly, in white truffles.

This is especially important since thiophenes contain carbon and sulfur, which are the two ingredients essential for life. The most likely source of these chemicals seems to be biological processes of primitive lifeforms; however, they could have been formed after a meteor impact too.

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While this is a major step in the hunt for Martian life, it is still not concrete proof. Washington State University astrobiologist Dirk Schulze-Makuch, who looked into how thiophenes came to exist on Mars said, “We identified several biological pathways for thiophenes that seem more likely than chemical ones, but we still need proof.”

Thinking thiophenes are biological on Earth is a given; however, we need more research to prove such a thing on Mars. If that turns out to be the case, it is likely that the thiophenes were made into being via bacteria, three billion years ago.

Back when Mars was a warm and wet planet, bacterial colonies could have existed. Then, Mars got dried up, and the triphones were left there until our beloved Curiosity dig them out of the mudstone billion years later.

Sadly, there is only so much we can learn from Curiosity’s sample. The Rosalind Franklin Rover, scheduled for launch in July, might provide the information we need; however, as Carl Sagan said: "Extraordinary claims require extraordinary evidence."

So, how will we ever know for certain? Schulze-Makuch answers the life on Mars question by saying, “I think the proof will really require that we actually send people there, and an astronaut looks through a microscope and sees a moving microbe.”

The study was published in the journal Astrobiology.