They are at the right distances from their star for liquid water to exist on the surfaces of several of them. (sciencedaily.com)
«This is a roadmap to where water exists on the surface of the Moon,» said Ralph Milliken, an associate professor at Brown and Li's co-author. (sciencedaily.com)
«This is a work that can't exist on the surface of the world,» said Hiorns. (independent.co.uk)