[Pontiac]

Reactor heat to melt some water and turn to steam as propulsion into an orbit around the moon and we are off to colonizing space.

What do you do with the reactor when you have used up the water?

Who is going to operate and maintain the reactor? What happens if the reactor has an accident?

Nice idea but the devil is in the details.

[LesbianThespianGymnasticMidget]

Q) What do you do with the reactor when you have used up the water?

A) It is in space. Doesn’t really matter much but toss it into the sun if it bothers you and it is out of fuel or send it back out for another asteroid. Not a complicated setup: see: Direct Energy Conversion in Fusion Reactors, by Ralph W. Moir, Lawrence Livermore Laboratories, Livermore, CA

Q) Who is going to operate and maintain the reactor?

Robots. The RF round trip when it is way out there is too long for remote controls.

Q) What happens if the reactor has an accident?

A) Not much. It is in space. Not near space. Way way out there. Heck even if it went supercritical where k > 1 as in kaboom it would be a little flash in the sky. The scary thing would be if the asteroid hit the earth hence going for a lunar orbit. Not a big deal if we accidentally hit the moon.