The following article was written by Cassidy Frazee.
Science fiction and energy weapons go together like ham and cheese, peanut butter and jelly, bacon and everything else. Energy weapons have been part of the genre since H.G Wells’ “heat ray” in The War of the Worlds (of course, there was no visible energy beam, but this is true of most lasers too).
Energy weapons are the science fiction writer’s weapon of choice. They seem to be able to run forever (all you need is power from your ship’s drive), they have great range (especially in space), and the time on target can’t be beat (they have that “moving at the speed of light” thing going for them). And when it comes to all the things they can do… oh boy, are you in luck. You can stun, you can burn, you can drill, you can blow up, you can vaporize. You could probably cook your breakfast with them in if you felt like it (although your bacon might end up extra crispy).
Now, once again, I’m not going to talk about handheld laser pisols and ray guns. That’s for another article. For today’s lesson we’re going to talk big honkin’ energy cannons. The kind that cause death and destruction, and that are as common to spaceships as power windows are to cars.
Energy Weapon Basics
Ship-mounted energy weapons come mainly in two variants; one uses light (a laser), and the other involves some kind of particle beam. (There is a third; plasma weapons, and I promise I’ll say something about them.) Like ballistic weapons, energy weapons can be mounted in fixed a position (often in forward, port, and starboard batteries), or turreted for a better field of fire. Since energy weapons don’t need ammo, they can simply be plugged into the main engines or secondary reactors, and can start vaporizing enemy butt right away.
In a lot of fiction, how many energy weapons your ship can carry is limited by one of two things; how much energy it has, or how hull space it has. Often times, in fact, science fiction creates small, powerful ships overloaded with weapons (the U.S.S Defiant, for example). These ships are often over-powered, meaning that the multitude of weapons can be fired without taking any energy from other systems. It’s an uncomfortable environment for all aboard, but the crew is at least secure in the knowledge that they’ll very likely kick the butt of every enemy they encounter—just stay away from the Chin’toka system and you’ll be peachy.
The opposite of this is, of course, the weapon so big and powerful that you need an equally big and powerful ship to lug it around. It doesn’t do damage so much as it does overkill. We’re talking about taking out dozens of ships with one shot, or a even planet or star. And if you call it your Wave Motion Gun, well, no points for originality, but you’ll have something people live in fear of… at least until they build their own, which seems to happen a lot. These large weapons tend to draw a lot of energy from the ship’s other systems, leaving it vulnerable for a short time as the weapon charges, or as the ship recovers. The Excalibur, seen in the Babylon 5 spin-off Crusade, is a good example of this.
The Rule of Cool
The sad reality of energy weapons in science fiction, however, is that they usualy operate under the Rule of Cool, which, if I may quote, says:
The limit of the willing suspension of disbelief for a given element is directly proportional to the element’s awesomeness.
The Rule of Cool goes hand-in-hand with Bellisario’s Maxim (“Don’t examine this too closely—”) and tends to be one of the reasons energy weapons can do so many great things… because they do it with such awesomeness (unless you are the sort of person who believes that kinetic weapons are just better).
Now, this isn’t to say that energy weapons shouldn’t be used. If applied correctly energy weapons are extremely effective when it comes to shooting a long ways off very quickly. And lasers don’t suffer from the inverse square law, so they’ll keep that same power on that target no matter how far away it is. The beam may spread a little, but this also means keeping the beam on the target longer. And particle beams, while having a shorter range than a laser, as well as following the inverse square law, will do a lot more damage to the target as the particles being fired have mass.
Charged particle beams can also take out a ship through bremsstrahlug, or “breaking radiation”. Simply put, run your particles up to about a gigaelectronvolt (GeV) per nucleon, fire at your target, apply a couple of megajoules per square meter, and watch everything inside the target die. And die they will. Not just people, but electronics that aren’t heavily shielded will fry as well, since at 1 GeV the particles are acting like primary cosmic rays. How much radiation? About 500 Grays. How much do you need to kill a person? More than 30 Grays at one time will lead to the instant onset of radiation sickness, killing them in a day. You’d need a lot of shielding to defend against this type of weapon.
The Problem with Plasma
So what’s so bad about all this? Well, if you stay strictly in the realm of science fiction and do a lot of hand waving, nothing. However…
First off, energy weapons are, well, energy hogs, due mostly to their inefficiency. A lot of this inefficiency is due to heat produced by the system. With particle beams, you have to worry about a charge building up on the sides of your ship. This, in time, will start to bend your beams (and no that’s not a euphemism).
Oh, and that plasma weapon I was going to talk about… won’t work. Never, ever. Plasma loves to cool and expand to its surroundings very quickly—like now. Firing a bolt of plasma from a gun would be like firing steam, and would likely do as much damage. Unless you have enormous gravitational and electromagnetic fields holding it together—in which case you have a weapon you could call a “star”—you can’t use plasma for anything useful. And if you can control gravitational and electromagnetic fields then well, you just don’t need a plasma weapon.
So why use a plasma weapon? The Rule of Cool, or, even better, “Is vultus terribilis, ideo oportet operari” (“it looks awesome, therefore it must work”).
Energy Weapons in Science Fiction
Star Trek and energy weapons go hand in hand. The early ships (if you follow cannon) had lasers that were eventually upgraded to phasers (said name given because at the time Star Trek came along lasers had only been around for 5 years and Gene Roddenberry didn’t want people coming along in a few years going, “You can’t do that with a laser!”, so he made up the name to indicate the weapons would “phase” the beam frequency and thus interact with the wave pattern of any molecular form), and as the years rolled on, by the time frame of The Next Generation even the smallest Federation vessel possessed firepower that would put the old Constitution-class to shame.
Think I’m kidding? The Constitution-class heavy cruiser had 4 twin phaser emitters and 2 torpedo tubes. Later, the tiny Nova-class science/scout ship had 11 type-10 phaser arrays and 2 torpedo launchers. The tiny science vessel, with a crew of only 80, could kick the original Enterprise to pieces and steal Kirk’s lunch money.
Starfleet vessels were extremely overpowered in terms of energy weapons, but then every ship in that universe was that way. At another end of the scale is Babylon 5, which seemed to like big ships with enough weapons (and fighters, lets not forget the fighters) to be very dangerous engaged against each other; small, fast, heavily armed ships that are the epitome of cool with no sense of scale; and incredibly huge ships bristling with alien weapons and/or planet killers. (Though B5 does get points for ripping off the Alexei Leonov from 2010 when they needed a good design for the Omega-class destroyer.) The first group of ships are just powerful enough to take on each other in one-on-one space combat and let the battle be decided by numbers and tactics; the second group of ships are also good at taking on each other, and their lager numbers and kick-butt weapons are used to great effect when they begin encountering the third group. Of course, the only way to defeat the third group is to enlist more of the third group of ships, at which point the commander gets their back up and tells all these pesky aliens to ‘get the hell out of your galaxy!’
And that third group, notably the Vorlon and Shadow vessels, brings up a good point about the ultimate ship’s energy weapon: the Wave Motion Gun, the Planet Cracker, the Doomsday Machine, the ultimate weapon that’s going to make your enemy loose control of their bodily functions whenever they see you coming.
Blowing Up a Planet
Lets get this out of the way right now. Yes, you can blow up a planet with energy: all you have to do is supply enough power to overcome the binding energy of said planet (the force keeping it together), otherwise gravity just pulls it all back together.
So how much is that for, say, the Earth? 2e32 Joules. That’s a 2 followed by 32 zeros, or 200,000,000,000,000,000,000,000,000,000,000. Or, to put it in a way that makes more sense, start gathering 1 megaton hydrogen bombs. When you have 57 quadrillion of them, you can blow up the planet. What does 57 quadrillion look like? That’s 5.7e16, or 57,000,000,000,000,000 bombs. Right now the whole nuclear arsenal of Earth is about 100,000 megatons, so you have your work cut out for you.
One other thing to keep in mind; if you do get all your 5.7e16 1 megaton bombs together and set them off, it’ll still take a few minutes for the Earth to come completely apart. If you wanna kick it Death Star style, you’re going to need a lot more energy.
And while we’re on the subject of the Death Star, individual beams of energy do not come together in the middle of nothing, where there is no focus. They will not build up into a big ball of kaboom, and shoot off to kill your planet. It just won’t happen. Rule of Cool notwithstanding.
So there you have it, energy weapons really do have the potential for huge destructive power. They also have incredible range and accuracy, and the advantage of requiring no ammunition. However they are also power hogs, and are completely theoretical. Nobody has yet figured out how to build a phaser or a disruptor cannon. And if they did, it’s not likely to be as effective as a ballistic weapon, or a nuclear missile, traveling at incredible speeds through space.
For the purposes of science fiction, however, energy weapons are very useful and very cool. And according to the Rule of Cool, the more awesome your energy weapons are, the more an audience will set aside their disbelief and become absorbed in a universe of impossible wonders.
A note of thanks to the site Atomic Rockets, by Winchel Chung, which was used extensively for background on much of this article. I would also like to thank Memory Alpha and Memory Beta for information on Star Trek ships and weapons, and The Babylon Project for information of the Ships of Babylon 5.
This article was written by Cassidy Frazee.
More in this series:
SciFi Weapons: Ballistic
SciFi Weapons: Missiles and Nukes
SciFi Weapons: Sidearms