The discovery of strange, mineral veins on Mars has planetary scientists buzzing. And no wonder: the find may shed new light on the Red Planet's watery past and could even help reveal whether Mars was once habitable.
NASA's Curiosity rover spotted the prominent veins in "Garden City." That's the name scientists use for a geologically rich site on towering Mount Sharp (Aeolis Mons), a mountain that rises almost 3.5 miles off the Martian surface.
A composite image of the veins was made by combining 28 separate photos taken on March 18, 2015 by the right-eye camera of the rover's Mastcam instrument.
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This March 18, 2015, view from the Mast Camera on NASA's Curiosity Mars rover shows a network of two-tone mineral veins at an area called "Garden City" on lower Mount Sharp.
"Some of them look like ice-cream sandwiches: dark on both edges and white in the middle," Linda Kah, a member of the Curiosity science team at the University of Tennessee, Knoxville, said in a written statement.
According to Kah and her colleagues, the veins -- which jut out 2.5 inches above a patch of eroded bedrock -- likely formed when fluids moved through cracked rock and deposited minerals. The light veins are made of calcium sulfate, which has been found by the rover in other nearby locations, according to the researchers.
The dark veins? They're a bit of a mystery.
“There’s something very different of these veins than what we have seen prior [sic],” Kah told the Los Angeles Times.
The researchers hope further analysis will yield new clues about the chemical make-up of the fluids that deposited the veins, as well as the changing environmental conditions on ancient Mars. So far, they believe both types of veins formed after the mud in a lake at Mount Sharp's base dried up and hardened, Space.com reported, and the dark veins were deposited prior to the light ones.
The finding adds to a growing body of evidence suggesting that ancient Mars had key ingredients for life. Just last week, Curiosity discovered a biologically useful form of nitrogen in samples of sand and mudstone.
The rover landed on Mars on August 6, 2012 and reached the base of Mount Sharp on September 11, 2014.