At the base of Mount Sharp, NASA's Curiosity rover has been exploring the dusty planes of Mars for signs of past life. There's already mounds of data suggesting the Red Planet was once a suitable environment for microbial organisms, and a new sample collected by the rover suggests water most definitely existed.

Through a new low-percussion drilling technique, Curiosity collected a sample from "Mojave 2," which found that a large amount of jarosite, a sulfate mineral that forms in acidic environments, was present. Curiosity has found signs of water on Mars before, but the newest sample indicates much more acidic conditions compared to samples NASA's rover has tested at other drilling sites.

NASA scientists aren't sure what to make of Curiosity's new finding, which is still being tested. On the one hand, the site may have been influenced by sediments deposited there as Mount Sharp took shape, or it could indicate fluids soaked the site much later. The "Mojave" site itself is an area of intense interest for NASA scientists because of its "slender features," which may indicate an ancient lakebed.

The picture above is a cropped view of a terrific picture NASA released. You can see the area where Curiosity used its gentler drilling technique, which scientists are using because of the fragile Martian environment.