Mariner 8/9

Mariner Mars 71

Mission Profile

Mariner 8 and Mariner 9 were twin NASA spacecraft launched in May 1971 aboard Atlas LV-3 Centaur-D1A rockets to conduct the first orbital survey of another planet — Mars. Mariner 8 was lost when its Centaur stage malfunctioned and tumbled into the Atlantic Ocean shortly after launch. Mariner 9 successfully entered Mars orbit on 14 November 1971, becoming the first spacecraft to orbit any other planet, and spent nearly a year mapping 85% of the Martian surface at resolutions of 1-3 km. Arriving during the global Martian dust storm of 1971, Mariner 9 waited patiently for the dust to clear before beginning systematic surface photography, ultimately revealing volcanoes, deep canyons, ancient river channels, and polar ice caps that transformed understanding of Mars's geological history.