I know that if you evaporate a molecule of water, that it must be 100C in order to be gaseous, so that it will take that heat with it if it wasn't already that temperature. This has a cooling effect if, for example, you're standing around wet.
I also know that if pressure is reduced then boiling temperature is likewise reduced, and the same for increasing pressure.
What I'm unsure of is whether reducing pressure changes the 100C that gaseous water must be.
In particular, in a vacuum water would basically instantly boil. Say due to the strength of the vacuum the boiling temperature is -50C. Does the gaseous water still need to be 100C, or has that temperature also been reduced? Would the water molecules that are boiling at -50C still need to be 100C to be gaseous, and so each one takes 150 degrees of energy with it when it evaporates in the vacuum? Or has the 100C been reduced to -50C, so the boiling water is already energetic enough to be gaseous, and does not extract any additional energy from other nearby matter?