Joseph Nebus wrote:
In the midst of a discussion over on rec.arts.sf.written I ran
across a point about Skylab that I hadn't noticed before. Following
the end of the third and most confusingly numbered astronaut mission:

After the crew had returned to earth and the
end-of-mission engineering tests were finished, flight
controllers vented the atmosphere from the workshop, oriented
the cluster in a gravity-gradient-stabilized attitude with the
docking adapter pointed away from the earth, and shut down most
of its systems.

http://history.nasa.gov/SP-4208/ch19.htm

OK, but why vent the atmosphere?


I suppose they might have been concerned with moisture condensation
(especially on the electronics) and pressure excursions caused by the
fact that they were no longer actively maintaining the internal
temperature. Those are just guesses though.