Additional proof has been discovered by NASA's Mars rover, Curiosity that supports studies the planet once held oxygen. Rocks on Mars reportedly contain manganese, which could only be possible if oxygen is present in the atmosphere.

Back in 2013, the Mars rover named Curiosity identified a huge amount of manganese. According to early studies, the element should not have been there. Analysts now conclude that the discovery is proof that the atmosphere of planet Mars once carried oxygen. The discovery was found on the formation called "Caribou."

"If we could peer onto Mars millions of years ago, we'd see a very wet world," stated Nina Lanza, researcher from Los Alamos National Laboratory. "Yet we didn't think Mars ever had enough oxygen to concentrate manganese - and that's why we thought the data from Caribou must have been an error."

Following the discovery, Curiosity was sent out on the search for manganese. A chemical analysis tool called ChemCam was added to the rover. This tool vaporizes rocks using a laser. Surprisingly, the samples taken by the Mars rover using the ChemCam also contained manganese.

Dr. Lanza now suggests that the sun's ionizing radiation split water molecules, which left hydrogen and oxygen in the atmosphere. As Mars has no magnetic field and has a low gravity, the hydrogen atoms would have floated away. The oxygen atoms on the other hand would have been absorbed by the rocks.

Where oxygen is found, life could exist. Yet for the rock containing manganese, which could point to the presence of oxygen in Mars' atmosphere - the finding is still not enough. Further analysis of the planets' minerals are needed for conclusive evidence.

"This tells us that Mars has evolved very differently than we thought it did," explains Dr. Lanza, adding, "We need to start looking for different types of minerals and other evidence about Mars's past."