As far as I know, the big damage from Nuclear Weapons planetside is the massive blastwave that can pretty much scour the earth, with radiation and thermal damage bringing up the rear.
But in space there is no atmosphere to create a huge concussive and scouring blast wave, which means a nuclear weapon would have to rely on its all-directional thermal and radiation to do damage… but is that enough to actually be usful as a weapon in space, considering ships in space would be designed to handle radiation and extreme thermals due to the lack of any insulative atmosphere?
I know a lot of this might be supposition based on imaginary future tech and assumptions made about materials science and starship creation, but surely at least some rough guess could be made with regards to a thernonuclear detonation without the focusing effects of an atmosphere?
How about a railgun with a nuclear payload? Breach the hull and the nuke would work again
With a hull breach the atmosphere within leaks out and I doubt there would be enough oxygen in the ship to really help with detonation. Maybe some self sealing projectile with a nuclear tip but really any traditional explosive would work fine in that case as the ship would act as a sealed canister
I think you overestimate how fast the atmosphere would leak out, or underestimate how fast a nuclear blast goes off. You could detonate the nuke before air really has a chance to start leaving behind the wake of the projectile moving at Mach 12 or whatever. The hole left behind i don’t think would change how the explosion worked inside the ship.
How would oxygen help with a nuclear detonation?