Is this organic compound a clue of early Martian life?
A global team of astrobiologists claim that organic molecules found by NASA’s Curiosity Mars rover could be proof of life on Mars.
In a research paper published in the journal Astrobiology, the team claims that the presence of “thiophenes,” which are special compounds present in coal, white truffles and crude oil back on Earth, could be an indication of ancient life on the Red Planet.
“We recognized several biological pathways for thiophenes that appear more likely than chemical ones, but we still need evidence,” Lead author and Washington State University astrobiologist Dirk Schulze-Makuch said in a statement.
The group, though, isn’t jumping to any deductions just yet.
“If you discover thiophenes on Earth, then you would think they are natural, but on Mars, of course, the bar to verify that has to be quite a bit higher,” Shulze-Makuch added.
Though thiophenes are made up of two bio-essential elements, sulfur and carbon, it’s still very possible they could’ve been made during meteor impacts that heat sulfates to high temperatures — a possible clarification the researchers are also bearing in mind.
If the compounds were truly a sign of life, they could’ve been the outcome of bacteria about three billion years ago breaking down sulfates — or otherwise could have been broken down by the bacteria.
But, again, it’s still too early to draw conclusions.
The Curiosity rover studies compounds by breaking them down into pieces. The forthcoming European Space Agency’s Rosalind Franklin rover, though, could fill in the gaps with its Mars Organic Molecule Analyzer (MOMA), which doesn’t use the same breaking technique as Curiosity.
What has Schulze-Makuch most excited is the prospect of finding differing ratios of light and heavy isotopes in compounds, the outcome of organisms breaking down elements and “a telltale signal for life,” as told by the researcher.
“As Carl Sagan said ‘extraordinary claims require unusual evidence,’” Schulze-Makuch said. “I think the proof will really need that we actually send people there, and an astronaut looks via a microscope and sees a shifting microbe.”