There are a lot of different concepts explored within the Star Wars universe, some of which are more philosophical, while others are more practical. Despite the galactic setting of the narrative, a lot of Lucas’ concepts are similar to our real-world concepts, which implies that the unknown universe is not as different as we might think. In that context, we are going to talk about why Lightsabers turn off when you drop them, comparing this concept to a very similar one involving regular knives.
There is no exact in-universe explanation for the Lightsabers turning off when dropped, but besides George Lucas making it like that, we assume that it is due to safety reasons, i.e., to avoid accidental injuries because the Lightsabers are very dangerous.
Saying that, getting into the physics of fictional worlds often turns into a seriously prolonged debate so make sure you win this one by reading further into this article!
What are Lightsabers and how do they function?
A lightsaber, also known as a laser sword (but only among those that are unfamiliar with it), is a blade-like weapon used primarily by the Jedi, the Sith, and other Force-sensitive beings in the Star Wars franchise.
A lightsaber consists of a plasma blade, which is powered by a kyber crystal, that was emitted from a usually metal hilt and could be turned on and off at will. It was a weapon that required skill and much training, and was greatly enhanced when used in conjunction with the Force. The lightsaber is a weapon usually associated with the Jedi – some even believed it to be a Jedi-exclusive weapon – but it is also used by the Sith and other characters (e.g. General Grievous).
Lightsabers were generally used for both offence and defence, depending on the situation. A lightsaber could cut through virtually anything, from flesh to blast doors, but it wasn’t omnipotent. The only known ways, though, to block an incoming attack of a lightsaber was with a weapon made with material that conducted energy, such as an electrostaff, a Z6 riot control baton, some rare metals, or another lightsaber.
When used defensively, a Force-sensitive could deflect blaster bolts with a lightsaber, and with skill, could even reflect the shots back toward the shooter or some other target. Experienced Jedi could even employ their lightsabers to absorb Force lightning. Most practitioners used one single-bladed lightsaber, though some used double-bladed lightsabers or even multiple lightsabers at once. A lightsaber can also come in a variety of different colours, which you can read about here.
Lightsaber fighting techniques are divided into seven forms (I-VII).
How long can a lightsaber stay on?
This is a big question for Star Wars fans, mostly because there is no definitive canon answer and several contradicting theories. Some statements from the expanded universe claim that a lightsaber can run practically forever and that, although it does lose energy, it has a self-charging (closed system) mechanism that makes it last forever.
The fact is a bit different. Namely, a lightsaber’s power cell is enormously powerful and a lightsaber can go a very long time without being charged, but it’s not nearly forever. So, just remember to regularly maintain your lightsaber and you’re good to go for a while.
Why does a lightsaber turn off when dropped?
As we’ve said, a lightsaber is a weapon that can be turned on or off using a switch on its hilt. This is why the lightsaber carriers can carry the weapon around without fear of being hurt by it, since a lightsaber won’t turn on by itself. So, why do they turn off when they fall out of the carrier’s hands? There are two explanations.
The first one is very simple – because George Lucas made it like that. Namely, there is no precise in-universe explanation that tells us why lightsabers turn off when dropped. This means that George Lucas wanted it to be like that. As the sole creator of the franchise, Lucas has as much liberty as he wanted and it seems that he found it practical to execute this lightsaber mechanism in that manner. This might not seem logical to someone, but there’s really not much one can do about it – just as liquid water is wet, a lightsaber turns off when dropped.
We can, though, assume why that is like that, i.e., why Lucas made such a decision. Namely, there is one thing we people know when dealing with knives – if a knife is falling down, never ever try to catch it while it’s falling. Why? A free fall is rather unpredictable and the knife’s blade can seriously injure you if you try to catch it during the fall. Now imagine that same thing, but with burning plasma that can cut through blast doors made out of metal. Not pleasant, right?
We don’t know whether George Lucas had this in mind, but the reason why lightsabers turn off when dropped is definitely safety, since that way, they won’t harm the carrier or anyone else for that matter. Certainly, a Force user can throw his saber and keep it turned on using the Force, but that is a personal decision by the carrier of the lightsaber. Again, we repeat, we don’t know whether this is the actual reason, but it seems quite probable and we are of the opinion that it could be correct.