Matt Zeitlin: Impetuous Young Whippersnapper

Ned wonders why spaceships always have self destruction buttons. Aside from the obvious silliness of having the self destruction sequence be so loud – which is clearly just a cinematic necessity – the real question is whether or not the “advantages of being able to detonate your own ship at any second are surely outweighed by the risks associated with rigging the entire thing with powerful explosives. What if something catches on fire?”

This sounds reasonable enough, but that’s only assuming that the self destruction mechanism is a bunch of “powerful explosives.” The way I understand it, most spaceships (in movies anyway) are powered by some sort of reactor (nuclear or otherwise) that, without many complicated controls and backups, will overheat and explode. To self destruct, then, you merely have to stop controlling the reactor, let it overheat and then have it blow up. Now, there are obviously problems with having such a capability on your ship (what if someone accidently starts it?) but it’s considerably less dangerous than rigging your spacecraft with a bunch of TNT.