Mariner 8 and 9 were virtually identical and designed to continue the atmospheric studies begun by Mariner 6 and 7, and to hopefully map over 70% of the Martian surface.
The primary objectives of the Surveyor program, were to support the Apollo landings by: (1) developing and validating the technology for landing softly on the Moon; (2) providing data on the compatibility of the Apollo design with conditions encountered on the lunar surface; and (3) adding to the scientific knowledge of the Moon.
After viewing the Apollo spaceport being built in Florida, President Kennedy flew on to Huntsville, Alabama. There, during a tour of Marshall and a briefing on the Saturn V and the lunar-rendezvous mission by von Braun, Jerome Wiesner interrupted Von Braun in front of reporters, saying, “No, that’s no good.” Webb immediately defended von Braun and lunar-orbit rendezvous. The adversaries engaged in a heated exchange until the President stopped them, stating that the matter was still subject to final review.
“I would like to reiterate once more that it is absolutely mandatory that we arrive at a definite mode decision within the next few weeks. . . . If we do not make a clear-cut decision on the mode very soon, our chances of accomplishing the first lunar expedition in this decade will fade away rapidly.” Wernher Von Braun June 7, 1962.