Take Back the Sky

by Jeff Cunningham

Welcome to the first in a series examining the real-life science behind Joss Whedon’s not-quite-science-fiction-more-of-a-western Firefly and its follow-up film sequel, Serenity. First up, we’ll be looking at a staple of pop-culture sci-fi that, interestingly enough, is only rarely seen in Firefly and Serenity: lasers, phasers, energy weapons, and other PEWPEWPEW!

In the Verse

First, let’s define conventions. We’re defining energy-based or directed-energy weapons as arms that emit focused energy (such as a laser) in an aimed direction at an intended target instead of propelling a projectile (such as a bullet) at it. This rules out the mysterious handheld device used by the Hands of Blue as well as the “sonic shotguns” used by the Alliance in two episodes (each of which we could easily devote an entire installment of this series to). After that, we’re left with only two instances in the series in which energy weapons appear and are utilized:

• The Lassiter, a priceless antique laser pistol from the collection of one Durran Haymer before being stolen by the crew of Serenity and Yolanda/Saffron/Bridget. We’re told in the show that its value stems from its historic significance as the forerunner of modern (in their time) laser technology.
  

  Courtesy of FOX, “Trash”

• The personal sidearm of one Rance Burgess, brutal rancher-baron. He was quite proud of it and its “auto-aiming scope”.
  

  Courtesy of FOX, “Heart of Gold”

The Science

There’s actually a large number of different technologies that fall under the category of energy weapons–there’s more than one way to make a laser. In general, they all work on the same basic principles.

The word “laser” is actually an acronym for “Light Amplification by Stimulated Emission of Radiation.” What’s that mean in Captain Dummy-talk? Well, it has to do with the way that the light itself is generated. All manmade light happens when matter (often a gas) is “excited” or infused with energy from a power source. This energy causes the electrons orbiting the atoms that make up the medium to jump upwards into a higher orbit, further away from the nucleus of the atom.

An atom, infused with energy from an outside source, jumps to a higher orbit.

If that sounds confusing, imagine having a weight on the end of a string and swinging it around your head. You have to keep swinging it at a certain speed in order to keep it from falling down. If you want to let out some of the line and swing it further and further out, you’ll also have to swing harder. The further that that weight “orbits” around the nucleus (your head), the more energy has to be put into that string and the weight.

The thing is, eventually, these electrons lose this extra energy and go back down to their original orbit. That energy has to go somewhere, though, so they pay it back in the form of a photon–better known to you and I as light. This is how everything from flat-screen TVs to flourescent bulbs work.

What makes lasers special is how they control the release of those photons. For one thing, the amount of energy put into the medium to excite the electrons is carefully managed so that all the electrons are elevated to a specific orbit so that they all release the same amount of energy as photons. These photons will then all have the same wavelength or color. Additionally, the release and emission of these photons is timed so that they all move in unison in one, focused direction.

That’s the basic principle behind how lasers work in theory. In practice, it takes a very complex setup of high-precision mirrors, exotic gases, superconductors, and sophisticated power sources. It takes a lot more than a AA battery to PEWPEWPEW, and the size of the systems required to store and manage that much energy alone is simply too great to fit into a handheld weapon. Portable, personal laser weapons are impossible with current technology.

What’s more, they’re also impractical. It takes so much energy to burn a hole in something when it’s so much easier to just blow a hole in something. This is probably why everyone in Firefly carries ordinary projectile weapons (guns) instead of phasers or blaster pistols. Using an energy-based weapon to kill someone is a huge, mammoth level of overkill–like using an atomic bomb to start a campfire.

It also explains the context of the few times that we see energy weapons in the show. Think about it: They’re only owned and brandished by the wealthy upper-class of the Verse who want to show off. It seems that, even in the future, it’s difficult to pack that much energy and the means to control it into a handheld device (remember, both weapons from the show each suffered a power failure when fired), so they’re probably too expensive for everyone but the upper crust. It seems that, in the Verse, laser pistols are a symbol of excess for its own sake, the future’s equivalent of the golden toilet.

Come to think of it, he kinda looks like he could use one about now.

Now, before we can call this “busted,” there’s another thing we have to consider: while personal laser weapons are highly impractical and implausible, that doesn’t mean we can’t just live with the large size of these devices and find a use for them. See, if size isn’t an issue, such as with a fixed ground station, then they’re perfect for use against airborne targets. Laser beams travel at the speed of light, so not only do you not need to aim ahead of the target nor account for wind, but there’s no supersonic craft nor missile that can travel fast enough to outrun it. Also, because there’s no momentum involved, such as with propelling a bullet, there’s no recoil–shame that handheld weapons are off the table for now.

The U.S. Navy’s experimental ship-board Laser Weapons System, or LaWS. Why they don’t curb their propensity for needless acronyms and just call this terrifying thing a “laser” is beyond us.

There’s already a number of devices either currently existing or in development along these lines. Among the more impressive examples is the creatively named Advanced Tactical Laser. Many of you may be familiar with the AC-130 Spectre gunship, a large transport airplane modified with the addition of high-powered long-range cannons. Its fearsome firepower has been showcased bombarding ground targets from the air in popular video games and recent films. The United States military, in it’s never-ending quest for bigger booms, saw fit to try replacing the Howitzer cannons with a 100-kilowatt chemical oxygen iodine laser (COIL). Instead of blowing up an entire city block as a speck in the sky, this will allow the same aircraft to punch a hole in a single tank a few inches wide from five miles away and 10,000 feet up with no collateral damage, then shoot about a hundred more with similar precision.

“I have a warship in deep orbit, Captan…”

Energy weapons exist in an even more advanced state on naval testbed ships, as you’ve already seen, and are undergoing evaluation at civilian airfields as a means of intercepting incoming missiles. Again, these systems are huge, some as large as six city buses. There is, however, a scaled-down mobile version called the ZEUS, which is fitted onto a Humvee and used to detonate bombs from a safe distance.

It combines two things Jayne loves: options, and not exploding.

These weapons, unlike the “luxuries” glimpsed in the series, seem not very far removed from the shipboard weapons seen in the film. Here’s an adrenaline-charged refresher:

Now, the “pewpewpew” that we see the Alliance ships firing are probably not energy weapons–remember, lasers travel at the speed of light in a continous beam more like the beam that the Reavers fire at Serenity, not in a bolt that moves slow enough for your eyes to track (and for Han Solo to duck his head and avoid in a certain, much-debated scene). No, chances are, the purplebellies are using simple, high-powered cannons and guns, which are no less dangerous in space (one itty-bitty hole in a spaceship is enough to endanger the lives of all onboard). The bright, fast-moving objects we see on-screen are probably tracer rounds, which are visible because they’re intended to be to help the gunners aim.

Of more interest to us is that weapon that the Reavers manage to hit Serenity with at 1:48. Again, it fires continuously, so it’s obviously an energy-based weapon. The only thing wrong with it is that we actually see it–aside from special exceptions having to do with the conditions of the medium it’s passing through (air), all lasers and energy weapons are invisible like the LaWS firing you saw earlier. If a squad of stormtroopers succeeded in the first-ever kill in Imperial history, there’d be no way to figure out who fired the lucky shot! We’ll allow Joss Whedon that this is science fiction, though, and things just need to look cool.

No, the weapon that shot Serenity out of the sky was likely not a laser, but an entirely different class of energy weapon called a microwave cannon.

Yes, microwave weapons work on exactly the same tech that heats your Ramen–and yes, there’s been some rather frightening studies done in microwave emitters that literally cook people alive as a means of non-lethal riot control. The Active Denial System heats water in the skin to cause intense, incapacitating pain without lasting burns or damage. What the military has (fortunately) focused more of its efforts on is more directed microwave beams, because of their ability to destroy unshielded electronics, such as the guidance systems of missiles and aircraft, by producing an effect like an electro-magnetic pulse, or EMP.

EMPs are another thing that many of us are somewhat familiar with from movies and video games: it’s a short, strong burst of electromagnetic energy which can take many forms, such as radiation, electrical fields, or magnetism. It’s true that they’re one of many terrible side-effects of a nuclear detonation, but few realize that they also occur in nature near lightning strikes and can also happen during power line surges. These bursts overload and fry the circuitry of sensitive electronics in both consumer and military devices within their range of effect, rendering them completely destroyed and useless. Hollywood tends to overstate the destructive potential of (as yet hypothetical) EMP weapons, showing such scientifically inaccurate consequences as everything from automobiles and wristwatches being neutralized—so much so, that, no joke, the United States Air Force hired Bill Nye the Science Guy to make an instructional video to train the Space Command Wing, called “Hollywood vs. EMP.” …Man, that was an awesome sentence to type. You don’t want to know what horrible, depraved acts I would commit to get my hands on a copy of that, but sadly, it’s not available to the public.

In any case, an electromagnetic pulse is just that—a pulse, much the same way that an explosion is a “pulse” of hot gases. It’s a bomb utilizing a force that can’t be focused like a microwave beam can, which would have a very similar effect on, say, an aircraft’s or spacecraft’s computer-aided flight controls, or “fly-by-wire” systems. This would explain why Serenity suddenly experiences a complete loss of control, prompting Captain Mal to shout “EMP!” as the ship drops out of the sky like a rock.

Conclusion

It will take a great deal of scientific and technological advancement before we could ever miniaturize laser weaponry into a portable, handheld form like the kind we see in Firefly. The reason we don’t see it that often in the show is not necessarily because it’s impossible, but because it’s unnecessary to start with if you’re in an Alliance-friendly bar come U-Day. Thus, the final grade is that “Joss got it right.”

As for the weapons in the space battle, particularly the beam fired at Serenity, the film not only got it right, but, notwithstanding artistic license in making the beam bright and visible, deserves extra points for scientific accuracy.

Verdict: Science is shiny!