The lightsaber is arguably the most iconic weapon in all of pop culture. And yet, we have no idea what it is. For almost 40 years, the Jedi’s more civilized weapon has captured audience imaginations, but we still don’t know how the weapon really works. Most people would probably just say, “It’s a fantasy movie. Why do you care what a lightsaber is made of?” If you know my show, you know why.

In my latest Because Science, I’m taking a look at the only aspect of lightsaber physics that we haven’t covered before: chemical composition. I’ve always said that lightsabers are plasma weapons, but it turns out that lightsaber color proves it.

Because lightsabers are glowing, intensely hot things, the swords can’t be lasers, nor can they be light-based weapons, George Lucas. This really only leaves plasma, which can in fact glow the colors we see lightsabers glow, like Luke’s classic green or Mace Windu’s greenscreen purple. This, combined with the fact that Star Wars may be set in a galaxy far, far away but is still presumably in this universe, means that lightsabers are most likely weapons that utilize the plasma of gases we already know of here on Earth.

To find of which gases and why, you’ll have to watch my latest episode above!

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