Water in Mars?

A rocky outcrop on Mars has sent a shot of excitement through the scientific community with the evidence it provides of an ancient riverbed -- Martian "water transport" -- according to NASA.

NASA's Curiosity rover has sent back pictures of a section of the Martian surface called Link, an outcrop of rocks whose surface is not coated in the ruddy dust of Mars but is exposed and clean, the space agency says. 

As the Los Angeles Times' Science Now reported Thursday, the combination of sandy rock and large pebbles tells a story of an ancient river, with rocks that traveled far, bumping into -- and smoothing -- one another out.  It was water, not wind, that created that rocky scenario on Mars, scientists said.

Water flow in Mars

Link, says NASA, shows rock formed by water deposits, made up of smaller, rounded rocks cemented together. "Water transport is the only process capable of producing the rounded shapes of clasts [gravel fragments] this size," according to NASA. 

As of Thursday, Curiosity was 2 to 4 miles from a triangular network of channels, an alluvial fan. Another indicator of ancient water activity on Mars, the slope looks as though flowing water may have spread material downward.

Like other formations in this portion of Mars, by the way, Link gets its name from a noted rock formation in Canada.

In an earlier interview with The Times, Curiosity deputy project scientist Ashwin Vasavada explained that the landing site and Glenelg -- the formation where Curiosity is headed -- were named prior to the rover's landing.

"Both our landing site and Glenelg are within the Yellowknife quadrangle, named for the Canadian city that is the jumping-off point for expeditions that study the oldest rocks in North America," he said. "Glenelg and other features within Yellowknife on Mars are named for the geologically famous rock outcrops around the Yellowknife area on Earth."