RT Journal Article SR Electronic T1 Running Water Eroded a Frigid Early Mars JF Science JO Science FD American Association for the Advancement of Science SP 1496 OP 1497 DO 10.1126/science.300.5625.1496 VO 300 IS 5625 A1 Kerr, Richard A. YR 2003 UL http://science.sciencemag.org/content/300/5625/1496.abstract AB