A shadow is cast by the NASA rover OpportunityPhotograph: NASA/JPL/APCape St Vincent, one of the cliffs of the Victoria craterPhotograph: NASA/JPL/Cornell/ReutersThe Echus Chasma is thought to have held enormous quantities of waterPhotograph: ESA/Getty ImagesThe Echus Chasma, part of the planet's Valles Marineris regionPhotograph: ESA/Getty ImagesThe Victoria craterPhotograph: Science Faction/Getty Images
