How quickly will you actually freeze in space?

[Ulzgoroth]

Wouldn't Sealed be a good idea for anything exposing itself to vacuum? That would guarantee no unwanted fluid losses.

Body temperature dropping should probably not be happening unless your base species doesn't thermoregulate. Certainly for humans any significant change in core body temperature is a major problem.

It looks like, assuming human size and a surface temperature of 33-37C, you'd be loosing heat at 1kJ per second, which doesn't seem all that bad. Though it'd drain you pretty quickly. In practice, radiative loss might be lower than that because the skin can be allowed to cool below core temperature, but I don't know how low that can go.

Overheating is definitely a potential problem, but I don't think humans actually generate a kW of heat constantly. And equilibrating with the sun isn't a big deal either...the equilibrium temperature of a black-body at earth orbit appears to be about 5 degrees centigrade.

Huh. Am I doing something wrong? This looks too easy.