Phases of water

These are Japanese Macaques, or Snow Monkeys. They live in the cold mountains of Japan, and in the winter, they spend a great deal of time in volcanic hotsprings like the one above. Interesting fact about Macaques: They wash their food before eating it, like humans and raccoons and no other animal in this wide world (that we know of, yet).

But that's not why I'm here. Rather, I'd like to point out the phase transitions of water taking place in this picture - you see all three: Liquid, solid, and gas. These are the three states of matter we are very familiar with on this Earth. There is a 4th state, the most common in the universe in fact: Plasma, i.e. what makes up stars (superheated gas phase changes into a plasma). Plasma does not exist on Earth except when we, Godlike, make it. Still, it only lasts for a few moments and then reverts back to a gas.

Phase transitions, as you know, are a function of temperature - that is, each element or molecule will go through a transition of phase with a corresponding temperature change. Hotter temperatures will lead to gases and plasmas, cooler temperatures to liquid and solids. Liquid is the weak leg in these transitions, as there are very narrow bands for each element/molecule where it can exist as a liquid. Solids and gases exist in a far wider range of temperatures. So, consider yourselves blessed beyond belief that we live on a world where water can exist naturally in a liquid state - the foundation of life, in fact (or so we believe for now).

I bet these monkeys appreciate it.