Had the interest in the Space Race not diminished after the Moon Landing in 1969, and investment at Nasa continued at similar rates as before, could there have been a Mars Landing in the 20th Century?
"Interest" both in the general public and in political circles was declining well before the Moon landing in 1969. NASA's budget had peaked in 1965 and had been falling already and the 'achievement' of the Lunar goal only accelerated that trend. People were tired of the "Space Race" and even more so the budget it needed and had other priorities they wanted addressed. There just wasn't any way to maintain the "Apollo" level spending or support. Also there was ongoing (since about 1964 but increased after the Apollo 1 fire) Congressional resistance to any NASA "beyond the Moon" (and specifically Mars) planning or spending.
Part of the problem was how NASA had been reorganized and rebuilt to actually accomplish the Lunar goal within the timetable given and how after that point NASA was no longer capable of operating any significant program without "Apollo" levels of support and spending. This is fairly effectively illustrated with the Shuttle program and was something NASA has yet to fully 'un-learn'.
A Mars landing in the 20th Century is "possible" but not really probable under the circumstances. A possible outcome is a joint US/USSR mission but in context that takes a lot different political and social background to get to happen.
If so, when? Could the US have pushed for it in the 80s? Is there even a possibility of it becoming a reality in the 70s? What about the Soviets, if losing the Moon pushed them to try for Mars, could they ever hope to achieve that?
A possible US Mars program would take a couple of decades at least due to the increased complexity and danger of the mission and of course there's likely to be less support and funding so that would also slow things down so having a US mission before the 90s is unlikely. The 70s is out due to lack of technology and capability, the 80s is possible but the most likely would be the early to late 90s IF there's enough support to start at the end of the Apollo program.
The Soviet space program was always more reliant on military support and funding and frankly there's no "good" reason to go to the Moon let alone Mars so it's not likely they could have gotten much further than they did OTL.
He made a LOT of assumptions to get that background and frankly it's pretty clear that going to Mars ONCE is about all they manage and even then there's even LESS in-space infrastructure than OTL and nothing to really fall back on once that's all done.
Randy
