Hi Guys

Robert Heinlein and Arthur C. Clarke did a lot between them in the late 40s, early 50s to promote the realisation of space travel in the next generation. In his 1949 novel "Prelude to Space" Clarke describes the first moonflight in 1978, while Heinlein covered the same topic with "The Man Who Sold the Moon" [also 1949] and in his Foreword to the short story collection of the same name he lists 1978 as his best guess.

Clarke imagined a two-stage nuclear ramjet/lunar lander system, while Heinlein described a huge chemical rocket a lot like early suggestions for "Apollo" which featured winged landers.

Clarke imagined an international effort funded by subscription and government funds. Heinlein imagined a private effort also part funded by public subscription/shares, plus USAF funds. Hmmm... common theme there.

Clarke's system was fully reusable, catapult launched and the nucleus of an Earth-Moon transport system. Heinlein's was a one-shot effort, followed up by catapult launched, orbital-refuelled "shuttles" that built the first base, "Luna City".

Both Clarke and Heinlein imagined a very rapid expansion into Space. Heinlein imagined Luna City by ~ 1980, followed by a GEO station ["SupraNew York"] and an L1 Spaceport to support a chemically propelled Lunar transport system. Both imagined missions to Mars and Venus by 1985, with Outer Planet missions by 1990, or so.

In his 1949 story "Earthlight" Clarke imagined a Solar economy so well developed by c. 2015 (~ 40 years after first Lunar missions) that it could contemplate war with Earth.

Heinlein, of course, has extensive development. In "Farmer in the Sky" he imagines terraforming of Ganymede beginning in 1998.

Where did it all go wrong? The Moon was reached 9 years early, but abandoned. Mars is actually furhter away in technology terms than it was in 1969. What happened?

Adam