>Next, let’s consider Mars. Mars is the underlying design case for the Starship, although Starships that go to Mars will probably be of a customized nature. Whi

>Next, let’s consider Mars. Mars is the underlying design case for the Starship, although Starships that go to Mars will probably be of a customized nature. While the Moon takes about 3 days to get to, Mars takes 4-10 months. Launch windows to Mars only open every 2 years, so even if Elon has 1000 Starships ready to go, they can only go every 2 years. and here i think Musk genius of targeting Mars instead of Moon shows again. Moon business case wouldn't support, while Mars does support the nuclear powered ships. The Starship is of the size to allow sufficient shielding for propulsion reactor. To avoid the "once in 2 years launch window" limitation an additional 3km/s delta-V is needed, and nuclear will get you that and would speed-up the flight in the standard window. Cutting some time from 3 days for Moon isn't really worth the nuclear hassle, cutting half from months long jorneys to Mars and ability to launch practically anytime - that changes everything for Mars. Stacking several Starships - lower ones with reactors, the upper - with people, one can decrease the amount/weight for the shielding. Going ionic thrust propulsion powered by the reactors one can get even faster. All this tech - nuclear propulsion and ionic thrust - had been tried already, so i think it is no less doable for SpaceX than the Raptor with its hot oxygen resistant superallow.