Star Trek‘s phasers have a top setting that will vaporize a human:
That’s not just overkill, that’s an insane level of overkill. It’s like using a TOW anti-tank missile to target an individual.
And this is one of the things that Star Trek got wrong. Not that it’s necessarily impossible for a weapon the size of a keychain to vaporize a human, but that the process of vaporizing the human wouldn’t utterly trash the surroundings. Face it: you’re converting, oh, 180 pounds of water to steam, and converting the calcium in the bones, the metal and plastic in his clothes, tools, weapons, etc. into plasma. And if the target is also holding a phaser, you’re converting that into vapor, which means that its battery (or whatever the power source is) is going to explode.
Phaser-vaporizing someone on board a spaceship is going to be a disaster, because by converting 180 pounds of water into steam, you’re increasing the volume by a factor of around 1,000. Imagine if the room the target was in suddenly found itself loaded with 1,000 more people. The pressure will blow the hull apart. While a blaster will simply poke a hole in the target, maybe burning their clothes.
Star Trek always made the result of someone getting vaporized pretty… well, sterile. Zap, bright light, gone. But it wouldn’t be like that. If you want to know what someone getting phasered at full power would look like, YouTube provides. Behold the phenomenon of the “Arc Flash,” where enough electrical energy can be dumped into a human to convert said human into a steam explosion. Obviously, this might be considered slightly grisly, so gather the kids around (occurs at 1:14; you can adjust settings to .25 speed to watch the guy go from “normal” to “Hey, he’s a glowing blob, just like in Star Trek” to “Where’d he go?” in three frames):
It’s kinda unclear just what the hell happened here, but it sure looks like the guy was converted into mostly a cloud and a bit of a spray. In any event, there’s no missing the fact that something really quite energetic happened to the guy. The captain of the Klingon scout vessel vaporizes one of his crew on the bridge, they’re going to be scrubbing it down for *days,* assuming that the steam and overpressure doesn’t kill everyone else on the bridge.
It turns out that the arc flash did not vaporize the worker:
(Hat tip to Nyrath.)
To be fair, phaser vaporization looks a lot like transporter teleportation, and I’m sure that saved some money on special effects.
A phaser magically dumps all its energy into the target.
A real video of a similar event will be mainly leakage, so the environmental changes will be largely down to leakage.
I roughed out the vaporization energy at 180MJ. About 45 kilograms of TNT. The volume increase isn’t really 1000, it’s about 24. One litre of water becomes 24 litres of steam. Nevertheless, the blast from a magic phaser will be about 45 kg of TNT’s worth, which would indeed wreck the place.
https://www.youtube.com/watch?v=Q7-uJhssw_U
In real life need at least 400 kg of TNT worth of blast to deliver enough energy to the human to vaporize it. (1 ton: https://www.youtube.com/watch?v=FAYVMXYYAp4) The damage from the human itself isn’t going to be noticeable. Regular lightning doesn’t vaporize people, so imagine super-lightning with enough current to do so. Whole streets of windows would shatter, at the very least, just from the lightning.
For comparison, a modern rifle cartridge delivers roughly 2 kilojoules of kinetic energy, 1/100,000th the energy needed to vaporize a human.
The original Star Trek got on with the story as well as saving a lot of money with very simple effects. A room with a big TV screen? It’s a starship bridge, now get on with the story. Captain Kirk’s image goes fuzzy, like a TV screen between channels- he’s teleported. Get on with the story. He’s holding a small briefcase? It’s full of antimatter to blow up a planet. Get on with the story. Phasers got the victim offstage as reliably as Davy Crockett Indians falling out of their tree- now you can get on with the story.
The first Star Wars and Star Treks got on with the story a lot better than the sequels.
I like David Drake, but I don’t want to see a movie about dealing with vaporized redshirt goo clogging everything on the Enterprise. Star Trek screenwriters aren’t as good as Drake anyway.
*You can get 1L of water to become 1000L of steam, but A: you’d have to superheat the water to 16 million kelvin, the same temperature as Sol’s core, and B: this is plasma, not steam.