Posted: Sat, Jun 26, 2010, 9:32 AM ET (1332 GMT)
New, separate studies have found evidence that liquid water was found throughout Mars early in its history, and that water may have flowed much more recently. French researchers using observations by NASA and ESA spacecraft have detected clay minerals at several sites in the planet's northern lowlands, according to a paper published in Science. Such minerals, found in abundance in the planet's southern highlands, are formed in the presence of water. A Brown University team, meanwhile, found evidence of more recent liquid water by documenting dozens of valleys in the planets mid-latitude regions, some of which are up to 50 meters wide and several kilometers long. Those valleys, scientists said, were created by water melting from glaciers during the planet's so-called Amazonian epoch, several hundred million years ago. That finding was reported in the journal Icarus.

Related Links:

•  SPACE.com article
•  Spaceflight Now article
•  BBC article
•  NASA/JPL press release
•  Brown University press release