NASA's Mars rover Curiosity has uncovered strong evidence that water flowed on the Gale Crater which is the site of rover's field. This was some while before the rover completed its first year on Mars.

An international team of scientists says that evidence has been identified for a potential source for the ancient water that glaciers flowed down the slopes of Mt. Sharp which is a 60 mile wide mound that is at 18,000 feet from the crater floor.

This could suggest that early Mars may have been neither warm and wet nor cold and dry, suggests Cornell University planetary scientist Alberto Fairén.

The evidence is received from a close study of detailed images of Mt. Sharp which were beamed back by NASA's Mars Reconnaissance Orbiter and the European Space Agency's Mars Express orbiter.

The Gale Crater lies in a region which is just south of the equator and is a part of the geological boundary between the southern highlands and northern lowlands of Mars.

There are other researchers who have seen evidence for glacial action at other places along transition regions from highlands to lowlands as well as in Gale. The glaciers are believed to build and vanish as the climate of the planet responds to a pronounced wobble in Mars' axis, the tilt of which ranges from 25 degrees to 45 degrees. Every few million years, this wobble brings so much chill to the equatorial region that it snows and polar ice melts to add water vapour to the atmosphere.

The most compelling evidence according to scientists comes from the three or four particularly pudgy rocky material which are about half a mile to over a mile wide and about 3.7 to 5 miles long. They have a resemblance to a rock glacier found in a valley in Chugach Mountains in Alaska.