Since its dramatic touchdown in August, NASA’s Mars rover Curiosity has delivered tantalizing clues of what’s to come as it seeks to determine whether its carefully chosen landing zone has ever had conditions favorable to microbial life. 

Some of Curiosity’s findings support discoveries from the earlier Phoenix Mars lander mission, about a class of mineral salts known as perchlorates, as Samuel P. Kounaves of the Phoenix Mars Lander Wet Chemistry Lab and Tufts University explained at the Annual Meeting. 

Artist rendering of the Mars rover Curiosity on the Martian surface.
Credit: NASA/JPL-Caltech

Perchlorate is an energy source for some bacteria on Earth, and it was discovered on Mars by the Phoenix mission, suggesting that perchlorate could have the potential to support subsurface life on Mars. Kounaves and his colleagues recently discovered what appears to be Martian perchlorate in a Martian meteorite that landed in Antarctica. These findings, together with results from Phoenix and now Curiosity, which has also found perchlorate-related compounds at its landing sites, raise the possibility that perchlorate could be relatively common on the Red Planet.

John Grotzinger, a project scientist at the Mars Science Laboratory and professor of geology at the California Institute of Technology briefed the audience of a special Topical Session on Curiosity’s latest activities. After finding heavily fractured rocks filled with mineral veins indicating the long-ago presence of water, as well as rounded balls of rocky material that may have once been worked over by water, the Curiosity team pinpointed a drilling site and has, for the first time, begun to pull up powdered rock for further study. 

The rover’s long arm is now processing the sample and, through a series of “tai-chi like motions” will deliver the material to other instruments on board, Grotzinger said.