4 huge ways Empire Strikes Back changed the rules of Star Wars starships

Star Wars did not invent the word “hyperdrive.”

The word has been kicking around in science fiction magazines since the 1930s, perhaps most prominently in the fiction of Isaac Asimov. (Asimov didn’t invent the concept either — it’s hard to say who did.) But like George Lucas, Asimov's casual assertion of faster-than-light tech into a story that wasn’t about that tech makes it work. For most of us, the spaceship nomenclature of Star Wars isn’t why we like the movies; the tech is just kind of there. The first rule of spaceship tech in Star Wars is a little like Fight Club: We don’t talk too much about spaceship tech in Star Wars for fear of ruining the magic.

Having said that, did you ever notice the starship rules of Star Wars became a little more ironclad in The Empire Strikes Back? Here are four important precedents the 1980 film set for the future of the franchise.

Welcome to Star Wars Week! To celebrate the 15-year anniversary of Revenge of the Sith (May 19) and the 40-year anniversary of The Empire Strikes Back (May 21), we're talking about our favorite sci-fi franchise for nine days straight.

4. The Empire had limited knowledge of space — Part of what makes space travel in the classic Star Wars trilogy unique is that you get the sense that nobody has a complete idea of where everything is. The prequels and the sequels changed this a little bit: In the prequels, Obi-Wan and Qui-Gon are pretty familiar with a general “map” of the galaxy. And by the sequels (specifically The Force Awakens and The Rise of Skywalker) we've all become very preoccupied with what is or isn't on known star charts.

Leaving aside who even made these star charts for a second, it's clear throughout the original trilogy that nobody knows shit unless they land on the planet and check it out. The opening crawl of Empire tells us Vader is sending probes out into the galaxy to track down Luke Skywalker. These probes aren’t mapping a planet from orbit and looking for lifeforms or heat signatures. They have to actually get down there on the surface, fly around, and take pictures.

Even when Vader’s fleet rolls up on Hoth, General Veers tells Vader they’re using something called Com-Scan to find stuff. According to various canon sources, Com-Scan is a computer system that correlates different kinds of astronomical data to approximate where things are at any given time. In other words, it’s not a magical “sensor” or “scanner” found in other science fiction like Star Trek. If the Empire wants to know where something is, they have to send a probe down to photograph it or use an extrapolating computer system that may or may not be giving them the entire picture.

3. Crippling big starships wasn't that hard — Technically speaking, the concept of the “ion cannon” wasn’t introduced in The Empire Strikes Back, but you certainly don’t remember anybody talking about it in A New Hope.

According to background information, all those Y-wing starfighters that helped attack the first Death Star (and valiantly got exploded) were equipped with ion cannons. However, this fact is never mentioned in any of the dialogue, and everybody generally accepts that Y-wings rocking ion cannons is a very old retcon. (Wookieepedia also agrees that Empire is the “first appearance” of the ion cannon.)

Unlike most tech in Star Wars, there’s a rare moment of exposition in Empire in which Leia actually mentions how the ion cannons work. It’s going to fire some bolts from the surface of the planet and disable the big Star Destroyers. We’re not talking about the local bulk cruisers mind you, we’re talking about the big Darth Vader ships.

If you think about this ability relative to everything else we see in the first three Star Wars films, the ion cannon is freaking amazing. Essentially, it’s an EMP (electromagnetic pulse) weapon that works long range. The fact that the Resistance or Rebel Alliance never uses it again is pretty stupid.

An ion canon would have been pretty handy when those First Order Dreadnaughts rolled-up in The Last Jedi!

2. You can’t destroy shielded planets from space — Speaking of those Dreadnaughts and planet-killing Star Destroyers in The Rise of Skywalker, none of that would ever fly in The Empire Strikes Back.

One of the most interesting things about the invasion of Hoth is that the Empire has to do it the old-fashioned way. Vader is told the energy field is too strong for them to blast it from orbit, meaning they have to land and take Echo Base with AT-ATs and ground troops.

The specifics of how enemy soldiers can walk right through a shield generator capable of withstanding blaster fire from the air (and space) is a little confusing. It’s one of these limitations that seems to exist specifically to let the story happen the way it does. Even if we don’t really buy the wonkiness of the way the shield generator works, that’s not really the point.

You can come up with a million reasons why this could make sense. Maybe the energy shield blocks blaster fire specifically but allows other things to pass through it. In Rogue One, we saw a slightly rowdier shield that surrounded the planet Scarif, one that specifically allowed ships to pass through one part of it: the Shield Gate.

But the version the Rebels are using on Hoth seems a little more thrown-together than the one on Scarif. Then again, unlike the one on Scarif, the Rebels may have had more foresight. There's no obvious orbital Shield Gate as a really giant target.

1. The fastest hunk of junk in the galaxy — One of the most interesting debates about The Empire Strikes Back is centered on how much time actually passes during the film. Are Leia and Han on the Millennium Falcon for a few days? A few weeks? Months?

After Han realizes that they can't jump to lightspeed, they have to find somewhere to get the hyperdrive fixed. The specifics of hyperdrive repair are even less interesting than figuring out how the technology works, but what is interesting is something you've probably not thought about much. How does the Falcon get around when it's not traveling faster than light? What's the range of its "normal" engines?

Turns out, the engines Falcon uses to maneuver in normal space (Girodyne SRB42 sublight engines) are actually capable of propelling the ship across immense distances in a relatively short period of time. At least relative to the kind of technology we have today.

Even when Han is slumming it in normal space, we're dealing with a spaceship that is really fast. In A New Hope, you kind of get the sense that the speed-bragging about the Falcon is connected to traveling through hyperspace, but Empire is the moment where you really see how fast the Falcon is on its own. Sure, this obvious when the Falcon is outrunning TIE Fighters in the asteroid field, but it's even more impressive when you think about the trip the Falcon takes from Hoth to Cloud City.

Let's pretend that Hoth is Mars and Bespin (the home of Cloud City) is Earth. Right now, we generally think it would take either half a year to a year to fly to Mars with the kind of tech we have in 2020. Whatever is powering the Falcon's sub-luminal engines (not speed-of-light) must be pretty damn good because there's no way it took the Falcon half-a-year to get from Hoth to Bespin. And if it did, then my god, what did Han, Leia and Chewie eat? And where is my Disney+ show about the three of them hunting for food for a year in asteroid belts? Mynock stew anyone?

It's pretty clear that we're supposed to think that the Falcon got from one star system to another in no less than like a month. Here's what we know. The Hoth system is actually its own planetary system, but by the time the Falcon cuts loose from hiding on that one Star Destroyer, they're actually in the Anoat system.

Han says that Bespin is "pretty far" but he thinks they can make it. How far is pretty far? The distance between one planet or several? Well, legit canon actually claims Bespin is also its own star system. So that means Han and Chewie flew the Falcon without hyperdrive between three different star systems in like a month.

In other science fiction that makes these kinds distinctions between sublight travel and some kind of hyperdrive (or warp speed or FTL) whenever you break down, you're totally stuck. But in Star Wars — or maybe just specifically on the Falcon — you can apparently traverse multiple solar systems using engines that are, in theory, not designed for interstellar travel.

This all brings us back to the idea of hiding in space from terrible Empires. If ships without hyperdrive can hop between solar systems, then ships with hyperdrive can hide wherever they want. The newer Star Wars films like The Last Jedi and The Rise of Skywalker make a big deal about hyperspace tracking and hyperspace skipping. But when it comes to the Falcon these newer movies forgot one amazing fact: The Millennium Falcon didn't need to be traveling at the speed of light to smoke the bad guys. Even without its fancy engine borrowed from sci-fi pulp magazines of the '40s, the Falcon was pretty damn fast.

Welcome to Star Wars Week! To celebrate the 15-year anniversary of Revenge of the Sith (May 19) and the 40-year anniversary of The Empire Strikes Back (May 21), we're talking about our favorite sci-fi franchise for nine days straight.