Good morning and welcome back! 

In this corner, weighing at 18.015 grams per mol, the "raining" champ- Water taking on the vaporous underdog, weighing in at 16.04 grams per mol- Methane! Let's turn down the temperature and up the pressure, because this is going to be interesting! Oh wait...what's this? Water has swallowed methane whole?!

Clathrates are water-ice cages- the "host"- trapping some sort of gas inside, usually methane, nitrogen, carbon monoxide, or even argon- which we call the "guests." This intricate lattice work is very delicate in its environment. So if any immediate change in temperature or pressure happens, the guest gas leaks out and the water cage collapses into, well, a puddle of water.

We can find large quantities of methane clathrates on the bottom of the ocean floor and as far north as the Canadian arctic. So what does this mean for other planetary bodies?

Supposedly, we have found evidence for clathrates on Mars- not in their full form- but rather the small, immediate release of methane vapors escaping the ice caps. Icy worlds, such as Europa or even Pluto may have these clathrate structures as well. Unfortunately, not much lab work has been done to find out if these structures can survive extremely low temperatures. If we do find evidence for these crystal-cages, this will give us one more glimpse into the evolution of gas-ice interactions to form our own Solar System!

And the other cool part? You can set them on fire! (with caution, of course...don't try it at home). 

Thank you for reading and next week, we'll take a look at some fun engineering with aerogel!