Valley Networks (image) Brown University Share Print E-Mail Caption Lyot Crater, rendered here with elevations exaggerated, is home to relatively recent water-carved valleys (denoted in white). New research suggests that water came from melting snow and ice present at the time of the crater-forming impact. Credit David Weiss/Brown/NASA Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.