The occurrence of Hesperian age (3.7-4 billion years old) standing bodies of water at the surface of Mars is a contentious issue, often conflicting with favored climate models.
Extensive lakes are proposed to have filled parts of Valles Marineris during this period, yet evidence for their presence and temporal continuity is poorly constrained.
In a study, Nicholas Warner and colleagues test the lake hypothesis within eastern Valles Marineris using a new suite of high-resolution imagery and topography data.