8 nov 98  a zuppero

The solar-heated steam rocket uses very thin pastic and metal foil reflectors to concentrate the sunlight on the water heater. The result is hot steam to propell payloads.
 


This solar option is more difficult to engineer than the nuclear option. The rocket nozzles must swivel in to point the steam away from the desired thrust direction. This is sometimes impossible. The solar collector mirror area must be about 1 kilometer across to give the same power as a 2 ton nuclear-heated steam rocket reactor. The sunlight must always be focused on the water heaters. The solar collector must not deform so much that it defocuses.

Solar- and Nuclear- Heated Steam Rockets Use Lunar Water Ice as Propellant to Open the Solar System for Human Invasion.

Even though steam rockets are relatively poor performers as rockets, they make up for it about 100 times over when they use the only abundant rocket fuel in space: water.

The nuclear-heated steam rocket is the only one with enough power to lift against the intense gravity of the moon. It shoves payloads into low lunar orbit. But solar heated steam rockets can take over from there, keeping the nuclear system captured deep in the strong gravity well of the moon.

The solar-heated steam rocket would take payloads from low lunar orbit to the Lunar and Earth escape orbit, to Earth orbit, to a communication satellite orbit, and can even send payloads to Mars. The Lunar and Earth escape orbit is special because it permits reasonable sized steam rockets to take 100 person sized payloads to Mars or the inner solar system.