Spotted by a high-powered orbital imager, they’re not the first deposits found on Mars of silica, a mineral used by some simple forms of life, including single-celled algae that evolved early in Earth’s volcanic past.
But the new deposits are the first from a locale with a definite volcanic pedigree, formerly rich in heat and water as well as minerals — a locale formerly suited, by any Earthly definition, for life.
Stand on the slopes of Nili Patera 3.7 billion years ago, and “you would see steam rising up out of the volcano. In the spots we see the deposits, that’s where the highest concentration of steam would be,” said geoscientist Jack Mustard of Brown University. “It’d be like standing on Hawaii, looking across a volcano, seeing the fumaroles where vapors are given off, or standing in Iceland where the hills are steaming.”
Mustard’s findings, co-authored with fellow Brown geoscientist J.R. Skok, were published October 31 in Nature Geoscience. His laboratory is among those that in recent years has processed an extraordinary flow of Red Planet data, returned by Mars-orbiting spacecraft and surface-exploring robots.
This data has moved researchers beyond looking for signs of water — the latest of which was reported just last week, by both the Spirit and Phoenix rovers — to evaluating potentially once-habitable environments in precise detail.
“It’s the most definitive hydrothermal system we’ve found on Mars. You can see the source of the heat, the driving of the fluids that left the deposits,” said Mustard. “In this deposit, you have the culprit right before you. In other deposits, they’re either sedimentary, or in the center of an impact crater. You have no idea how they happened.”
Red more at Wired
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