Henry Spencer wrote:


Note, in particular, that in the proposed Mars-mission profile, the
capsule has to go up to meet the MTV (Mars Transfer Vehicle) "in a
circular orbit of 800- to 1200-km altitude".


That's high enough to start worrying about the inner Van Allen belt.

Why so high?!? There's only
one reasonable answer: the MTV uses nuclear propulsion, and must start in
a "nuclear-safe" orbit, high enough that orbital life in the event of a
failure exceeds 10kyr.



It might not use nuclear propulsion, but rather nuclear electrical power
generation, which for a manned Mars mission would seem to be almost a
necessity. Of course their might be a Timberwind engine lurking out
there somewhere...for as excited as the military got over that thing it
seemed to vanished awfully quickly.
Of course knowing the current administration it will probably use the
Orion drive. Why? Simple, that breaks a treaty, and that's always fun to do.

Pat