David Bray wrote: > I'd go for burning hydrogen - not hydrogen fusion - if we can extract water > from the Moon with solar power as the initial kick-starter. We will need > the hydrogen for future rockets launched from the Moon's lower gravity to > Mars and beyond too... I think water is better used for people than for burning. There isn't that much of it out there. There are times you need the high thrust, but if you can use electricity instead, it's better in the long run (and on the moon, with 14 day 'nights' I think nuclear will win burning hycrogen may be needed for landings and maneuvering, but use magnetics for launching. David Lang