Volcano Lightning!

An epic volcano is erupting in Chile right now! There have been 2 massive explosions in the last week, and hot ash is dumping out of the top. The cloud of ash sometimes has lightning in it:

 

Yea this looks fake but it isn't

 Here's a detailed description of how lightning in a volcano works, but the basic principle is the same as regular lightning: there's a difference in charge that's so great that the charges come together violently.

Notice that each lightning bolt is connecting a heavily charged area to something else (source)

Why is there this difference in charge? Because of all the motion going on inside the cloud - the raindrops drag electrons downward with them, which leaves positive charges up top. Small note: positive charges cannot really move since they're from the protons inside of atoms - we get positive charges because of the absence of electrons (which are negative). Static electricity is a great example of this - when you rub your socked feet on the carpet, you're scraping electrons off the carpet and building them up onto yourself. Then you can get close to someone else and create a little lightning of your own :)

Step one: acquire electrons.

Lightning also comes with thunder, for a reason that sounds too crazy to be true: the lightning is so hot that it burns up the air, creating a temporary vacuum of empty air. In this case, vacuum doesn't mean like a vacuum cleaner; it means that the area is actually empty, there's not even any air molecules - space is the most common example. The air around that empty air fills in very quickly and that causes the noise of thunder!

The air is superheated and burned! Then the air collapses around it and you hear thunder. (giphy.com)