Pohl crater could be an intriguing site for a future Mars mission. This satellite image shows multiple ancient environments that a rover or astronaut could explore, all of which may have once been in contact with seawater. Pohl's crater rim cuts diagonally through the image; outside of it, to the upper right, is terrain that may have been scoured by glaciers where the ancient sea met the coastline. To the lower left, inside Pohl, are possible marine sediment washed up by the younger megatsunami; atop that surface appear to be mud volcanoes.