This Wednesday, all Star Wars fans shared in the joy of wishing each other a happy May 4th. Unsure of why the movie-themed phrase is thrown around this particular day? Check out this short article on the history of the pun and how and why it became the annual mantra for all Star Wars fans.
Although Disney holds a patent for a “sword device with retractable, internally illuminated blade,” we’re wondering if the lightsaber we see in films could translate to real life. According to VR developer Ben Ridout, who took it upon himself to describe how Disney’s technology works, their product “won't melt through metal blast doors, or cut off your hand, but it does feature an illuminated blade that will extend and retract at the push of a button”—which doesn’t cut it for us. So, how does lightsaber technology work according to the movies? Are there real-life lightsabers? Could there be?
Cue the Imperial March, and read on to learn more about one of Star Wars’ most famous props.
At the source of the lightsaber’s power and functionality is the kyber crystal. The kyber crystal, which is rare but found throughout the Star Wars galaxy, makes up the core of every lightsaber and has two properties that combine to make the crystals the key component behind the power of the lightsaber: Kyber crystals are inherently attuned to the Force, and they’re unmatched in their ability to channel energy and generate enormous returns.
But kyber crystals only focus and amplify existing energy—lightsabers need a source of power to function, just like any other piece of technology. The power cell needed is more or less a rechargeable battery—that’s it. Ideally, Jedi use Diatium cells (also known as a power core). When the lightsaber is activated, power from the cell is sent through a series of focusing lenses, converting the raw energy into dangerous plasma, which is immediately channeled through the kyber crystal via the energy gate.
And at the end of the hilt are the blade emitter, which converts the kyber crystal–enhanced beam of energy into a super-heated plasma blade, and the magnetic stabilizing ring, which gives that plasma blade its distinctive shape by keeping the beam of focused energy in check via a containment field, preventing lightsabers from passing through each other when they connect. Apart from these is the hilt itself, usually made of metal but occasionally of gems or even wood, and an optional belt clip. And, of course, no lightsaber would be complete without an activator to turn the weapon on and off.
When activated, a lightsaber sends a great deal of energy into a very small space. In order to avoid energy discharges that could cause damage to the weapon or its user, the power cell needs to be properly insulated in the hilt. Lightsabers work as complete circuits, and as such, need the circuit to be complete to operate.
So, how close can we get to the movie-style prop given our Earth-bound technologies and the laws of thermodynamics? The trick is harnessing the energy the lightsaber needs to perform the feats accomplished in the films. Once harnessed, the question becomes how we could possibly hold that much energy in our hands without its container being either ridiculously heavy, ridiculously large, or simply too hot to handle.
In 2020, Canadian engineer and CEO of Hacksmith Industries James Hobson created a plasma-based protosaber. (In the Star Wars universe, a protosaber is an archaic lightsaber that requires external power supply; the hilt of the blade is connected via cable to a power pack that is carried on the back or the hip.) Current understanding of plasma says that the substance can be held in a beam using a magnetic field; however, producing a strong enough electromagnetic field to contain a blade would require that it’s built inside of a box coated in electromagnets.
So Hobson and his team came up with an alternative solution to control the flow of plasma using laminar flow. Compressed liquid propane gas (LPG) provides Hobson’s protosaber with enough energy to power the superheated beam of plasma, which burns at about 4,000° F, allowing it to cut through many different materials. Different chemical compounds, such as boric acid, calcium chloride, strontium chloride, sodium chloride can be added to the beam to color it!
Combined with a computer-powered program that allows the protosaber to be run at the press of a button, this technology may be the closest thing we currently have to the lightsabers we see on the big screen. To see the protosaber in action—and see how it was built—check out Hacksmith Industries’ YouTube video here!
You, too, can explore some of the physics principles behind lightsaber technology with these hBARSCI products on light and optics and electromagentism!
