Technology

More than likely transporting enough nuclear materials to power a moon base would be exorbitantly expensive and dangerous.

From my calculations you would need at most a few hundred kilograms per year for such a reactor, perhaps even less than 100kg/year if they can use higher enrichment than normal.

At that weight they might be able to carry it in a manned craft to avoid it blowing up and being spread all over the place since manned crafts have a lot of safety features, including an ejection system to launch the people (and the uranium in this hypothetical case) safely away from an exploding rocket.

If you’re planning on building a reactor on the moon, it’s probably to probe the possibility of utilizing helium3 to create a fusion reactor.

A fission reactor and a fusion reactor are completely different things but you would need power to turn a fusion reactor and that could come from a fission one.

Which would help cut down on the need for liquid coolant.

As far as I know a lot, if not the vast majority, of the coolant you need is for sending the unusable heat away and that is basically the same between all turbine using power plants (from coal to nuclear), unless the fusion reactor doesn't need it.

I mean they do have easy access to an endless vacuum they can radiate heat to.

Radiating it to the vaccum is a lot harder than transfering the heat through heat exchangers from the inside water to outside water so being in a vacuum without rivers to use for cooling is much harder to get rid of heat than on Earth. They would probalby need pipes going deep underground or running across the surface with hot water to be cooled by the ground, which would need to slowly radiate it to space requiring a lot of piping if you produce a lot of power, before the water inside the pipes cool enough to be usable to cool the reactor again.