I’ve had my officers blown out of several ships so I’m pretty sure they can’t. And I’d like to know why they can’t! In Mount and Blade Bannerlord companions (the officer equivalent) can die, and they’re much harder to replace with people of similar qualify than the officers in Starsector. There’s excellent mercenaries for a temp replacement, and there’s also a ton of available officers hanging out in comms, in bars and even arising from meritorious action in the bizarrely named and badly overloaded intel page (which combines quest log, message log, several actions and a secondary map into one big blob of indifferent usability)
Officers are cheaper than ships and traditionally go down with the ship, but in this game they typically abandon their crew while saving their own skins!
In the immortal words of Elsa, it’s time to let em go