On May 7, 12:12*am, Doug Freyburger wrote:

*Solar cells should be plenty in Earth orbit for
station keeping and orbit maintenance but interplanetary missions would
work far better with more power available. *A nuclear reactor could
supply power for both the drive and the rest of the vehicle.

But how to get one safely aloft or enough infrastructure in place to be
able to build one from spaceborn raw materials ...

Well as mentioned in a previous post Russia will launch reactors
without problem. If you dont want to launch the fuel from Earth how
about Thorium. You could mine and concentrate it from the Moon.

A thorium reactor has the advantage of needing a particle beam to
operate so if the particle beam is switched off the fuel cant chain
react and have a meltdown, AIUI without the beam the fission slows
until the fuel cools, it's called a sub-critical reactor. Might be a
good safety option for a ship.

Another alternative, is a reactor using Plutonium as the core with
Thorium fuel. There is one running in Moscow. Although, with this you
would need the to have the russians ship the plutonium from Earth at
least.

Maybe the first industry on the Moon will be harvesting and
concetrating Thorium for Space reactors.