The curiosity rover found something that some researchers believe is consistent with the presence of early life on Mars. What the rover found was a compound called thiophene, an organic compound found on Earth in coal, crude oil, and white truffles. Thiophenes were discovered on Mars, and a researcher from Washington State University called Dirk Schulze-Makuch believes that the presence of the substance on Mars is consistent with the presence of early life on the Red Planet.
Dirk is working with other scientists from Berlin to explore some possible pathways for the origins of thiophenes on the planet. The work suggests that biological processes, most likely involving bacteria, may have played a role in the presence of the material in the Martian soil.
Dirk says that the team has identified several biological pathways for thiophenes that seem more likely than chemical processes. However, he says that the team still needs proof. The scientist notes that the bar to prove organic origins is much higher on Mars than it would be here on Earth. So far, the team hasn’t been able to exclude non-biological origins for the compounds on Mars.
One possible method that could have created the compound is meteor impacts. Thiophenes can be created through a thermochemical sulfate reaction involving sets of compounds being heated to 248F or more. For the biological scenario, the most likely process would involve bacteria that may have existed on the planet three billion years ago when the planet was warmer and wetter.
The bacteria could have facilitated a sulfate reduction process that resulted in Thiophenes. Other pathways where bacteria broke the thiophenes down is also possible. More details will be provided for the researchers by a future rover called the Rosalind Franklin launching this summer.