(Repost from RPG.SE, per the community's suggestion.)
A friend recommended I post this question here - said I'd be more likely to get a useful response than, say, from Reddit.
My question is: How would a nuclear explosion operate in the vacuum of space?
Battlestar: Galactica and Mobile Suit Gundam SEED both portrayed nuclear weapons (or fusion/fission technology in general) in an outer-space environment. In one episode of BS:G, the Galactica gets nailed by a thermonuclear warhead that managed to penetrate its curtain of defensive fire, but (to my surprise) the ship survived being crippled or destroyed outright.
I've been digging into a tabletop RPG system called Mongoose Traveller over the last few months. Its hard science fiction approach reminds me of The Expanse. The more I dig into it, I find myself daydreaming about the reality of combat in space. No atmosphere to conduct sound, so combat is mostly quiet; ship attack from long distances takes minutes, even longer at extreme ranges. Combat in a hard-sci environment takes on some qualities I'm not used to in most sci-fi settings, and I like it.
So, what about explosions, especially and specifically ones from fission warheads? I have a few specifics I'd like to get some insight on:
- How would a vacuum affect a nuclear explosion (or, really, any explosion)? Would the lack of atmosphere cause it to snuff out sooner? For a nuclear blast, which stages of the detonation/fallout would experience significant change? Would the effective blast radius be likely shrink or expand?
- Would the shockwave from a nuclear blast travel far through a vacuum, or would it exist at all? In general situations, I believe you'd see an explosion but hear and feel nothing; with something of this magnitude, is that still true? Is space truly a vacuum through which nothing can transmit?
- Traveller considers radiation exposure in open space as fairly harmful over short periods of time; without the proper shielding, space travel over long periods of time is extremely hazardous, and space walks without protective layering are reckless. Would the radiation released from a nuclear explosion be more or less considerable in a vacuum?
I appreciate your consideration, and any insightful answers (or even hypothesis) would be fantastic. I don't know much about physics really (outside of the enjoyable what-ifs I read from xkcd!) so I'm at a loss.