Mariner 6/7

Mariner Mars 69A / 69B

Mission Profile

Mariner 6 and 7 (Mariner Mars 69) were twin NASA spacecraft launched in February and March 1969 aboard Atlas LV-3 Centaur-D1A rockets for close flyby passes of Mars at distances of 3,400 and 3,500 km in late July 1969. Together they returned 201 photographs of the Martian surface, revealing both ancient heavily cratered terrain in the southern hemisphere and the strange featureless chaos terrain near the south polar cap that had no clear geological analogs. The combined mission nearly doubled humanity's photographic coverage of Mars compared to Mariner 4 and revealed the enormous diversity of Martian surface types. Mariner 6 and 7 data helped establish that Mars had no liquid water on its surface and reinforced the picture of Mars as a cold, barren world with a very thin atmosphere.