We also have water vapor, about 0.25% by mass. Significantly easier to get: a chemical reaction not inherently necessary, just filtering (you're not combining v

We also have water vapor, about 0.25% by mass. Significantly easier to get: a chemical reaction not inherently necessary, just filtering (you're not combining various elements of the air mixture, just taking one that's already there). Thus, no revolutionary breakthrough needed: just iterative optimization of water vapor collection. Of course, the efficiency of this bottle depends on https://en.wikipedia.org/wiki/Humidity https://en.wikipedia.org/wiki/Humidity - in a desert, with 0% humidity, there is very little to extract.