So, @KaTrian and I are writing a scene in our sci-fi WIP where a character is chased into the reactor room of a nuclear-powered space ship. We have a few questions regarding the practicalities of that scene. First, what kind of a reactor would a space ship have if it's roughly twice the size of the larger nuclear-powered aircraft carriers like the USS Enterprise? Would it be a pressurized or boiling water reactor, radioisotope thermoelectric generator, graphite-moderated reactor, or something else? How many reactors would it have? Bear in mind that the ship is space-to-space only, so it does not need the power of planet-to-space rockets and shuttles if that matters at all. Second, what possible consequences could there be if you fired a rifle near or at a nuclear reactor (the kind depending on what would be most likely on such a vessel)? Or threw a concussion grenade close to one? The lone character chased by the others essentially plans to hide close to one of the reactors, hoping that that way she could fire at her pursuers at will while they would have to pick their shots very carefully or risk causing a nuclear disaster that would kill them all. Now, for that to be even borderline plausible, we need to know a bit more about the design of such reactors and so far Google hasn't provided us with definite answers. In order to make small arms fire dangerous, should the chased character go directly to the nuclear core? Or is that too shielded well enough that no rifle could penetrate it, i.e. shooting at it would be perfectly safe? Should she head into the containment building? Which parts in a nuclear power system could cause a nuclear explosion (or some other such immediate disaster) if fired at/subjected to the blast of a concussion grenade? Thanks in advance!