Rust May Cover Carbonate Deposits on Mars

Peering under a thin layer of iron oxide, or rust, could reveal important carbonate deposits on the surface of Mars, a new study indicates. Finding the mineral could confirm theories that the Red Planet once had liquid water flowing on its surface.

Geologists know this from studying water-logged formations here on Earth, and have been looking for signs of carbonates on Mars for decades. They were unable to find it despite their best efforts, but a new study shows that that stuff may be hiding under thin layers of iron oxide.

Thus far, our neighboring planet has revealed only very small amounts of stand-alone carbonates. What experts believe is that the rest may in fact be just under our noses, so to speak. Future missions to Mars might help verify whether this hypothesis is true or not.

According to the team behind the new study, experts arrived at this conclusion by analyzing rock formations and minerals in the Mojave Desert of California, one of the driest places on Earth.

Arid conditions here are extremely similar to those on Mars. The main difference is the temperature – while the Mojave heat is nearly intolerable, the surface of the Red Planet can dip to minus 87 degrees Celsius. The mean temperature is minus 63 degrees Celsius.

“The plausibility of life on Mars depends on whether liquid water dotted its landscape for thousands or millions of years,” explains NASA Ames Research Center planetary scientist Janice Bishop, who is also based at the SETI Institute.

“It’s possible that an important clue, the presence of carbonates, has largely escaped the notice of investigators trying to learn if liquid water once pooled on the Red Planet,” she goes on to say.

Together with Ames planetary scientist Chris McKay, she collected sample from an area of the Mojave Desert called Little Red Hill earlier this year. They immediately made a potentially groundbreaking finding, Universe Today reports.

“When we examined the carbonate rocks in the lab, it became evident that an iron oxide skin may be hindering the search for clues to the Red Planet’s hydrological history,” McKay explains.

“We found that the varnish both altered and partially masked the spectral signature of the carbonates,” she adds. Biology-wise, the team also found dehydration-resistant blue-green algae, which somehow managed to survive in that extreme environment.

If Mars has liquid water in the past, and life did get a chance to develop during those eons, than it is conceivable that lifeforms may indeed survive to this day. With this in mind, the need for more exobiology missions to the Red Planet is becoming more and more intense.