it also depends on the time. If you freeze shortly, then water crystals will manage to build up within the cell.
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I guess for autopsy slow-freezing could still be ok, maybe aliens are even tougher than humans etc...
Similar matters were discussed in one of Heinlein's novels. I don't know the English name of the novell, but you may have read it also. There's guy, almost student, son of "brilliant scientist and his best female-student" won a lottery (inventing an ad slogan for "Sky Way soap") and got the space suit as second price.
As to slow and fast/shocking freezing, let me concretize.
I would prefer to store dead alien's bodies in fast-frozen state (with freezing speed approx 100degrees/second), not in slow-frozen: they would not be used as mashed beef, instead, they must retain their structures for my examinations.
Note that the aliens do not breathe our atmosphere.
Well, my fault. Any way, they wear no hermetic helmets or something like, so air pressure and temperature are suitable for them - you will not colonize Jupiter because of its high gravity.
It makes more sense to me to keep corpses in a containment facility rather than in the general stores ... Plus, the corpses would decay if they weren't somehow preserved.
Deep and fast freezing is the good enough way to preserve dead bodies, isn't it?
Yeah but containment doesn't mean cryogenic, it means containment, in other locked up.
I talked the same: before we can create suitable conditions to contain live aliens, we must have a storage for the bodies of dead aliens. And I know no method better than cryo.