The large impact crater known as Stickney is the largest crater on the Martian moon Phobos. Some scientists believe the grooves and crater chains are related to the formation of Stickney, whereas others think they may have formed as a result of the ejecta from impacts on Mars that later collided with Phobos. The lineated textures on the walls of Stickney and other large craters are landslides formed from materials falling into the crater interiors.