There are some pretty spectacular varieties of clouds out there, but it turns out you can also use simple physics to create a brand new one in your own mouth. Usually this ability is restricted to extremely cold weather - you know, when it's almost freezing outside and your breathe fogs up - but in this video, Physics Girl has hacked the science behind that trick to show you how to make your own cloud anytime you feel like it.
Now before you get started, we have to warn you that this process requires you to look pretty strange, so it's probably best to practice this in the comfort of your own home to start with (in front of a mirror if possible, so you can see your handywork). The first step is to click your tongue rapidly on the roof of your mouth for 30 seconds, with your mouth closed and full of air the entire time.
After that half a minute, you then need to pressurise your mouth. You can do this by holding your mouth closed tightly and then trying to blow out. Once that's done, you just need to open your mouth and watch that little cloud escape. Beautiful.
That all sounds pretty ridiculous, but we promise it really works! And the physics behind the trick is pretty simple too. As Physics Girl explains, when you click your tongue during the first step, it creates tiny water droplets in your mouth that can easily evaporate. These droplets create warm, humid air inside your mouth.
Then when you pressurise your mouth, it heats the air up even further. This is because of the old faithful gas laws, which tell you that as pressure goes up, so does temperature. That warm air now trapped inside your mouth can hold even more water vapour.
But as soon as you open your mouth, the pressure drops and therefore so does the temperatures. That decline, combined with the cooler air outside your mouth, causes the water vapour in your humid air to condense out into tiny water droplets, creating your own tiny cloud.
This is the same process involved in creating a cloud in a bottle, and, as it turns out, a cloud IRL. Watch the episode above to find out exactly how this works outside in the atmosphere, and to appreciate in video form just how cool this trick looks. You're pretty much guaranteed to be the most impressive person at your next party.