Researchers reveal that Mars may have hosted diverse environments in its ancient past. The scientists examined the rocks samples NASA's Curiosity rover gathered on Mars to arrive at this conclusion.
As part of the study, the researchers discovered a wide diversity in the minerals that were deposited in layers on the sedimentary rocks collected from the base of Mars' Mount Sharp.
The NASA Curiosity rover landed on the Red Planet's 96-mile-wide Gale Crater in 2012 and took another two years to reach Mount Sharp, which is located at the crater's center. Shortly upon its landing, the Curiosity rover found evidence that the Gale Crater was once home to a diverse environment and could have been a "lake-and-stream system" in Mars's ancient past.
"We went to Gale Crater to investigate these lower layers of Mount Sharp that have these minerals that precipitated from water and suggest different environments," the study's first author Elizabeth Rampe remarked.
Rampe also shared that these mineral layers were deposited roughly 3.5 billion years ago, at a time when the Earth was taking its first steps toward supporting life. The researchers posit that ancient Mars was possibly similar to the Earth in its initial days. The Red Planet's early environment was possibly even habitable.
Evidence Of Diverse Environment On Mars Found
The researchers note that the collection of minerals found in the four samples from Mars' Mount Sharp reveal that they precipitated into layers because of water presence. The diversity in the minerals layer deposits also reveal that the Gale Crater was home to not one, but multiple environments.
The sedimentary rock samples that contained the mineral deposits were drilled out from the base of Mount Sharp. The range of mineral deposits that were found in layers also hint at the presence of water around the rock base. This water had different pH levels and unpredictable oxidizing conditions. The rock samples also suggested that there could be more than one source region for the Marias Pass and Pahrump Hills regions' sedimentary rocks.
Different Minerals Indicate Different pH Levels
All the four rock samples examined revealed a wide diversity of minerals. Three of the rock samples were collected from the Pahrump Hills region, whereas the fourth was found in 2016 and named "Buckskin."
These rocks were then studied using the Chemistry and Mineralogy or CheMin instrument aboard the Curiosity rover. The researchers found that the base mineral's source was prehistoric magma, rich in magnesium and iron similar to the basalt rocks found in Hawaii. The scientists observed that more layers situated higher were composed of silica-rich minerals.