Salt streaks sign of present-day water flows on Mars

Salts deposited in dark streaks on Mars, such as these in the nearly 1000-kilometer-long canyon Coprates Chasma, are left behind by contemporary seasonal water flows, a new study suggests.

JPL-Caltech/NASA, University of Arizona

By Christopher Crockett

September 28, 2015 at 11:00 am

Liquid water might not be a distant memory on Mars. New data suggest water flows on the Red Planet even today. Seasonal dark streaks etched onto some slopes are coated with salts that need liquid water to form, researchers report online September 28 in Nature Geoscience. The Mars Reconnaissance Orbiter recorded spectra showing hydrated salts at four locations on Mars.

The salty trails appear annually, showing up only in warm seasons. Rising temperatures probably drive water to the surface, though whether the source is buried ice, local aquifers or something else is unclear.