Mysterious 'cauliflower-looking' formations on Mars could have been deposited by "ancient alien life" experts have said.
The deposits of opaline silica were initially spotted inside Mars's Gusev crater in 2008. At the time, scientists were unsure of what was responsible for these formations.
However, recent research in a Chilean desert suggests microbes could be behind the deposits, the Smithsonian reports.
In December, Steven Ruff and Jack Farmer from the Arizona State University published a paper explaining linking microbes to the silica deposits
Both experts arrived at their conclusions by making comparisons between Chile’s Atacama Desert, reported to be very similar in soil-type to Mars, and what was seen by NASA's Spirit Rover.
Their observations are of course an extrapolation of what they have seen on Earth.
Other cauliflower-esque formations, spotted in New Zealand and Wyoming, have also been linked to microbes.
However, other experts in the field warn against getting too excited.
“I don't think there is any way around using modern Earth analogs to test where Martian microbes may be found,” Kurt Konhauser, editor-in-chief of the journal Geobiology, told Smithsonian.
He added: "Having worked on modern hot springs, I have seen all forms of structures that look biological but are not.”