On Tue, Oct 31, 2017 at 9:02 PM, Kurt Feltenberger <xxxxxx@thepaw.org> wrote:

One of the common adventure hooks that I've seen is the "lost ship"; it could be a rumor of a ship from centuries past, a derelict that's found drifting in an asteroid belt that has no clues to its origin or age, or any one of a number of different plots, but they all have a common thread that the ship has been in space - vacuum - for a considerable amount of time.  Which leads me to wonder about what damage prolonged vacuum exposure might result.  What would weaken or fail, what would be ok, etc.  Granted, the materials science of the various empires, and Imperiums, probably found a solution, but what about the lower tech societies or if they didn't?  We know that some ships have been in service for decades or more, and then they're put in mothballs and stored at a depot, so something must have been developed.  I'm curious what this might be or the effects.


For ships being intentionally stored, no point in venting it to vacuum.  Hard on the internals, and then requires air or vac suits to get the ship  back into operation.  Although, if you are doing it intentionally, part of the storage procedure may be storing some large compressed atmosphere tanks in the hold, enough to get the ship back up to shirtsleeve operating pressure.  Or maybe not, and that's one of the things the yard tender carries around...


Ships being unintentionally stored due to death of the crew, still unlikely to be vented to vacuum, unless the crew vents it as a suicide move to try and contain some contagion.   That doesn't seem like a normal protocol, though. 


I suspect most ships don't have enough compressed atmosphere stored on board to vent the whole ship to vacuum, and then restore to normal pressure.  



That makes damage from space battles more dicey; if large sections of the hull get vented, the crew may be riding home at significantly lower air pressure, or some of those vented areas may stay vented or very low pressure (requiring airlocks to move in/out) until the ship can replace atmosphere.

Back around to the OP:  I suspect that vac storage is more a Hollywood convention to shorthand long duration, than an intentional practice.  

A ship might eventually leak down to vacuum, and depending on the seal quality, that might take months or years.  (I would suspect that leakage rate is a curve, with the rate slowing as the internal pressure drops.)  

Anybody got data on the rate at which we replenish the air mix on the ISS?

Dan





 
--
"Any sufficiently advanced parody is indistinguishable from a genuine kook." -Alan Morgan