Nixon says no to Mars
Von Braun had twelve astronauts leaving Earth orbit on 12 November 1981 aboard two nuclear ships. Seven months later Nixon put Mars behind a rigorous system of national priorities.
Eleven days after Apollo 11 splashed down, Wernher von Braun stood up in front of Vice President Spiro Agnew's Space Task Group and spent thirty minutes reading out a schedule. Two ships, each three NERVA nuclear stages bolted side by side under a four-deck mission module, 800 tons apiece at departure and three-quarters of that hydrogen. Twelve astronauts in two crews of six. Leave Earth orbit 12 November 1981. Enter Mars orbit 9 August 1982. Three men down in a 47.5-tonne excursion module for thirty to sixty days, a Venus swingby on the way home, Earth-orbit quarantine 14 August 1983. Paine, closing, put the cost at roughly $9 billion a year.
Nixon had set the group up by memorandum on 13 February 1969, with Agnew in the chair and Paine as NASA administrator. Budget director Robert Mayo attended as an observer and turned out to be the most consequential man in the room. Paine spent the summer courting Agnew, who used the Apollo 11 launch to call for Americans on Mars before 2000 — a misjudgement about whose enthusiasm was worth anything.
The refusal began in Congress, not the White House. On 29 July, before von Braun had even given the pitch, Senator Clinton Anderson — NASA's most dependable ally — said this was not the time to commit to a crewed Mars flight. Gallup that summer had Americans against a Mars mission 53 to 39. Mariners 6 and 7 flew past on 31 July and 5 August, sending back two hundred more pictures of craters and stripping out what was left of the biological argument.
The report went to Nixon on 15 September with a split personality. Paine's body text made Mars the destination of every option and offered a menu of paces: a maximum-rate landing in 1981, 1983, or 1986 — Agnew's preference — with a fourth option identical to the last and no date at all. White House staff bolted a conclusions section onto the front so the President would not be handed only ambitious choices: it conceded NASA could reach Mars inside fifteen years, then recommended sometime before 2000.
Mayo answered in numbers. On 13 November 1969 his office cut NASA's FY 1971 budget to $3.5 billion, a billion short of the request; Congress got $3.38 billion on 2 February 1970. The Saturn V line shut permanently and Apollo 20 was cancelled. Nixon's statement of 7 March never said no out loud — he said the United States would eventually send people to Mars — but space had to take its place "within a rigorous system of national priorities", which meant the same thing.
He approved the Shuttle on 5 January 1972; NERVA was terminated a year later. Von Braun's departure date arrived in November 1981 and nothing left Earth orbit. What flew that year was Columbia, 250 km up. Every crewed Mars architecture since has been drawn against a budget settled in 1970, which is why the rest of this timeline is robots.