Curiosity Rover Finds Vein-Like Rocks Seemingly Two-Toned in Color (LOOK)

While poking around at the base of Mars' Mount Sharp, NASA's Curiosity rover came across some two-tone rocks that appear to form a network of veins.

According to a news release from NASA's Jet Propulsion Laboratory (JPL), the rover snapped photos of the veiny rocks on March 18 and the space agency released them Wednesday.

Dubbed "Garden City," the ridges stand about two-and-a-half inches off the ground and appear to be darkened on the top and bottom and white in the middle, like a certain frozen snack.

"Some of them look like ice-cream sandwiches: dark on both edges and white in the middle," Linda Kah, a Curiosity science-team member at the University of Tennessee, Knoxville, said in the release. "These materials tell us about secondary fluids that were transported through the region after the host rock formed.

"At least two secondary fluids have left evidence here. We want to understand the chemistry of the different fluids that were here and the sequence of events. How have later fluids affected the host rock?"

Garden City is likely further evidence to support water's one-time existence on Mars, as such ridges typically form when such fluids run through them, leaving minerals behind in the fractures. The site is another justification for the Curiosity team's long trek to reach Mount Sharp, a giant mountain in the middle of the Gale Crater NASA targeted for the robot's ultimate destination.

Since arriving at the Pahrump Hills toward the base of Mount Sharp, mission mangers have collected samples now from three sites, each yielding different minerals.

"We investigated Pahrump Hills the way a field geologist would, looking over the whole outcrop first to choose the best samples to collect, and it paid off," David Blake, of NASA's Ames Research Center in Moffett Field, Calif., said in the release. "Telegraph Peak has almost no evidence of clay minerals, the hematite is nearly gone and jarosite abundance is down. The big thing about this sample is the huge amount of cristobalite, at about 10 percent or more of the crystalline material."