Mars Express uncovers ancient flood-carved chaos in Shalbatana Vallis
European Space Agency's Mars Express orbiter released high-resolution imagery of Shalbatana Vallis, a sprawling Martian channel near the equator, revealing chaotic terrain formed by catastrophic groundwater-fed floods about 3.5 billion years ago; the main channel is roughly 6 miles wide and plunges about 500 meters, with layered deposits and volcanic ash indicating multiple floods, lava flows, and erosion that point to Mars being warmer and wetter in the past and possibly hosting an ancient ocean near Chryse Planitia.