... beginnings of the planet, and ended sometime between 3.8 and 3.5 billion years ago according to accepted models) – the southern highlands were actually cold and icy. These areas acted as cold traps, giving rise to the accumulation of snow...
... acquired on sol 1041 of Curiosity’s mission (11 July 2015). Spirit was targeted to Gusev Crater on the edge of the southern highlands of Mars. Orbital imagery was suggestive of a past lake existing in Gusev Crater. What Spirit found upon landing...