NASA Says Signs of Liquid Water Flowing on Mars

[Valin]

NY Times
KENNETH CHANG
SEPT. 28, 2015


Dark narrow streaks, up to a few hundred yards long, are seen along many slopes on Mars including Garni Crater. The identification of waterlogged salts in these streaks fits with the idea that they are formed by the underground flow of briny water that wets the surface. Credit Jet Propulsion Laboratory/University of Arizona/NASA


Despite its reputation as a forebodingly dusty, desolate and lifeless place, Mars seems to be a little bit wet even today.

Scientists reported on Monday definitive signs of liquid water on the surface of present-day Mars, a finding that will fuel speculation that life, if it ever arose there, could persist to now. “This, I think, gives a focus of where we should look more closely,” said Alfred S. McEwen, a professor of planetary geology at the University of Arizona and the principal investigator of images from a high-resolution camera on NASA’s Mars Reconnaissance Orbiter.

In a paper published in the journal Nature Geoscience, Dr. McEwen and other scientists identified waterlogged molecules — salts of a type known as perchlorates — in readings from orbit. “That’s a direct detection of water in the form of hydration of salts,” Dr. McEwen said. “There pretty much has to have been liquid water recently present to produce the hydrated salt.”

By “recently,” Dr. McEwen said he meant “days, something of that order.”

(Snip)