NASA has announced this week that complex organic matter has been found in an ancient lake bed on Mars.
The material was found after the rover drilled into the surface of a 3.5 billion-year-old mudstone at the bottom of the Gale crater.
Researchers have been quick to point out that the discovery does not necessarily mean that there is, or has been, life on the red planet.
The groundbreaking discovery represents the best evidence yet that Mars was once home to lakes filled with the carbon-based compounds necessary for primitive life forms to develop.
Intriguingly, NASA scientists have been unable to determine how this organic matter originally formed, meaning that there is a chance that it was the byproduct of ancient organisms.
It may have also been deposited on Mars by comets or asteroids in the distant past.
Certainly, the presence of these compounds would have helped to sustain any life that did arise.
"We know that on Earth microorganisms eat all sorts of organics. It's a valuable food source for them," said NASA biogeochemist Jennifer Eigenbrode.
"While we don't know the source of the material, the amazing consistency of the results makes me think we have a slam-dunk signal for organics on Mars."
"It is not telling us that life was there, but it is saying that everything organisms really needed to live in that kind of environment, all of that was there."
“To me it is amazing that we can show we have organic matter preserved for more than 3bn years in these rocks,” said Kirsten Siebach, a planetary geologist who was not involved in the work at Rice University in Houston, Texas. “This is very promising for the preservation of potential ancient life on the planet.”
“These molecules could have been part of life, but they could also have been food for life,” Siebach added. “To know that the water really was full of organic molecules really opens up the different ways that life could have existed on Mars.”
