This map from NASA's Dawn mission shows the global distribution of hydrogen on the surface of the giant asteroid Vesta. Credit: NASA/JPL-Caltech/UCLA/PSI/MPS/DLR/IDA
A distinctive "pitted terrain” observed by NASA's Dawn mission on Vesta has also been seen on Mars. Credit: NASA/JPL-Caltech/University of Arizona/MPS/DLR/IDA/JHUAPL