BEN: "Your father’s lightsaber. This is the weapon of a Jedi Knight. Not as clumsy or as random as a blaster."
The lightsaber is probably the most legendary and recognizable piece of science fiction weaponry in history. Until recently, this weapon has completely stumped even the nerdiest of scientists. But now, thanks to some serious perseverance, the lightsaber might become a reality.
So, how does the lightsaber work, according to a Jedi Knight?
Well, according to the lore of the Star Wars Expanded Universe—all of the official novels, comics and television shows that make up the Star Wars story—a lightsaber is an energy blade essentially composed of a diatium power cell and crystals that focus the energy into a beam. The optimal number of crystals in a classic saber is about three. Makes sense to a bunch of aliens, I guess.
So, what would it take to make one here on plain old Earth?
Neil likes to remind people that lightsabers would not actually be made of light. If they were, the beams would just pass through each other like the light from a flashlight does. However, Neil suggests that at a high enough energy on the electromagnetic spectrum, you can get gamma rays and gamma rays will interact with each other creating a force. So, if you could design something that emitted high-energy gamma rays then, yes, it is possible to have your own lightsaber.
However, Michio Kaku has a different approach—he suggests using plasma. Plasma is the fourth state of matter and is essentially an ionized gas. Michio suggests that a lightsaber blade could be built from super-hot plasma. Michio would start with a fan in the hilt of the saber, to suck air into the weapon where it could then be superheated (to around twelve thousand degrees). Then, he would use an electromagnetic coil to keep the plasma contained on a ceramic rod. Ceramic is the material best suited to withstanding the high temperatures of the plasma. And lastly, he would power everything using trillions of nanobatteries!
So, there you have it! It sounds pretty wild, but it seems that lightsabers, made here on Earth, are not only possible, but could be here sooner than you think!
Want more Star Wars science? Find out if a planet can really have two Suns, like Luke Skywalker's home planet of Tatooine. And while you're at it, you might want to find out how long you'll have to wait until scientists discover intelligent life on other planets.