First things first: Happy New Year to everybody!
I have got a few questions regarding travel throughout the solar system within realistic timescales. Unfortunately I am not versed in orbital mechanics, and before I embark on months of possibly futile study I am hopeful that some of the bright people on this forum may be able to offer some advice on the following:
1) Using ‘realistic’ near term propulsion technologies (thermal nuclear rockets maybe? Suggestions would be welcome here as well), what would be the approximate travelling timescales for manned missions to the asteroid belt and the Jovian system beyond (specifically Europa)? The relative positions of Earth and the destination obviously introduce variations here, but can anyone give an approximate figure?
2) Jupiter’s gravity appears to make a return from the system back to Earth difficult. Could this problem be overcome using said propulsion technologies, or is this a show stopper for sample return or manned missions? (Assuming the radiation problem could be dealt with).
3) For long duration manned missions, extended exposure to microgravity will be detrimental to the crew’s health. As an alternative to the ‘spinning' of modules to create artificial gravity, would it be feasible to have the vessel accelerate at 1g (or thereabouts) for half the journey, the decelerate at 1g for the remainder? I guess a problem would be fuel and energy for continuous engine firing, but if these problems could be solved (nuclear or fusion power plants?), does anything speak against the concept?
I would be really grateful for some input on this, even if it is only point to some blatantly obvious thinking errors I have made. I am not afraid of equations either, if someone would like to suggest a few analytical means of getting to what am after.
Thanks in advance, I hope some lively discussion will ensue…