Freezing liquids in vacuum


I am afraid that you were in error in your response to a question about freezing liquids in vacuum. You responded that vacuum never causes liquids to freeze and that liquids exposed to space would always completely boil. You further said that the vapor would re-condense to a solid. This is not correct. It is true that vacuum is below the triple point of most liquids (the exception being liquid helium). But in order to boil the liquid still needs to overcome the latent heat of vaporization. As you correctly point out, space has no temperature or heat and is a very efficient insulator. The only source of energy is the liquid itself. Thus, the liquid cools as it boils and eventually freezes. This is why water (or pee) freezes when exposed to space