During its second encounter with Mercury on Sept. 21, 1974, NASA Mariner 10 took this picture of the planet South Polar Region. Many of the craters have denuded rims peppered by smaller craters.
Small Craters Peppering South Polar Region
During its second encounter with Mercury on Sept. 21, 1974, NASA Mariner 10 took this picture of the planet South Polar Region. Many of the craters have denuded rims peppered by smaller craters.