Since I’m not a clickbaiter, I’m gonna answer the question right away: no, lightsaber blades are not weightless, they have a mass. The rest of the article is about details of that fact and why it is so. So, hang tight.
But Laser Does Not Weigh Anything
While this might be true (even if you could somehow measure weight of laser or a light beam, it would be next to negligible), however, despite their name, lightsaber blades are not actually made of light or laser, but rather plasma. Now you can ask, isn’t plasma weightless as well?
Well yes, but actually no.
The original idea of the heaviness of lightsaber blades came from George Lucas himself. In one of the behind-the-scenes (“The Birth of the Lightsaber”) videos Lucas explicitly states that lightsaber will feel heavy and awkward in inexperienced hands.
But why is it so?
Yes, Mr. Lucas! Yes Science!
From a scientific point of view (please bare in mind that I’m not a physicist), any beam, whether it’s a condensed light, laser, plasma, etc., must be controlled by some other physical force, otherwise the length and power would be determined and limited only by its power source, crystals and output size of the hilt.
So, without those additional forces, it would be weightless indeed, basically like a flashlight – same weight whether it’s turned on or off.
However, since lightsaber blades are much more powerful and the blade has to be set to a specific length, there is a need for some kind of a field, specifically magnetic field.
Basically, the generated plasma blades are compressed in a strong magnetic field. This field causes a powerful gyroscopic effect that will effectively resist any changes in motion and velocity, thus giving it mass (of sorts).
So, while the pure plasma might be weightless, it’s indeed the magnetic field and gyroscopic effect that will increase the weight of the lightsaber.
So How Much Does a Lightsaber Weigh?
The answer to that question varies from lightsaber to lightsaber, since ever hilt is different and, in some cases, even the length of the blade varies.
But in general, considering that a standard single-blade lightsaber hilt weighs about 1 pound (453 grams) and the magnetic field around a plasma blade of 3 feet (0.91 meters) in length might weigh about 1-2 pounds (453 – 906 grams), the total weight of a lit lightsaber might be between 2-3 pounds, so close to a weight of a rapier.
When we consider the question of practicality, I’d say that lightsabers are very practical to carry around – you are basically carrying a hilt that weighs around one pound. This means it’s not very heavy to carry around all day and also takes very little space and doesn’t block your leg movement, so having it hanging off your belt seems like a smart choice indeed.
However, you need to make sure the crystals and electronics inside the hilt are functioning and in top condition. You don’t want your lightsaber to die in the middle of a fight, like a flashlight that fails to pierce the darkness during the worst possible moment.
Acrobatics and Stuff
So why did Jedi and Sith of old knew all these flashy acrobatics movements with blades that we now know weren’t really weightless, while the duels in OT (Original Trilogy) seemed heavy and slow?
Below are several explanations:
- Most Jedi of old were raised at a very young age in the academy and they were training with training sabers, which were very similar to real lightsabers in weight, meaning they were accustomed to the weight from an early age.
- Younglings could also choose to practice the art of the 4th lightsaber combat form of Ataru (The Way of the Hawk-Bat, or The Aggression Form) which primarily focused on aggressive acrobatic assaults and strikes.
- Most modern sword fighters will tell you that that your sword will get lighter in time. While technically a sword will have the same weight over time, your muscles and body will adapt to sustain extensive training with it, thus the feeling of it being lighter comes into play.
- We should also keep in mind that Obi-wan and Darth Vader were quite old in the OT and Luke didn’t have proper experience and training with a lightsaber, so none of them could afford flashy acrobatic tricks.
I believe this article not only answers the topic question but also provides some insight into how plasma beam can work as a blade. If we do someday invent functioning lightsabers, I hope the society will be morally and ethically ready for them.