Off the western flank of Elysium are the Hephaestus Fossae, seen in this image from NASA Mars Odyssey, with linear arrangements of small, round pits. These features are commonly called pit chains and most likely represent the collapse of lava tubes.
Off the western flank of Elysium are the Hephaestus Fossae, seen in this image from NASA Mars Odyssey, with linear arrangements of small, round pits. These features are commonly called pit chains and most likely represent the collapse of lava tubes.