Getting back to the earlier topic...I think I like the idea that Shaun Christopher's flight was at such relativistic speeds that he and his crew took years to complete it, and the Ares project could have been initiated in the intervening years (i.e. if the Ares 'third generation ion drive' was invented after Christopher's flight left).
Err, at relativistic speeds, it would take less than 90 minutes
to get to Saturn, and that's as seen by an Earthbound observer. A journey of years is more the sort of thing you'd get with today's technology. The Voyager
probes took 3-4 years to get to Saturn because they had a favorable planetary configuration to give them gravity assists. Cassini-Huygens
followed a more roundabout path, looping past Venus and Earth a couple of times to get onto the right trajectory, so it took nearly 7 years.
But there's no way a manned mission taking that long would ever be approved, even with cryogenic technology, because of the risk of cumulative radiation exposure. A manned mission to Saturn would have to wait for faster propulsion methods or a highly propitious planetary alignment.
Perhaps in the Trek timeline, ships were already sufficiently shielded against radiation even when Christopher's mission took place (as is implied in films like 2010
). Or, as you say, the planets were sufficiently aligned at the time.