What Would Happen If You Shot a Gun In Space?

Life Little Mysteries ^ | 2/17/2010 | Natalie Wolchover

[U-238]

Fires can't burn in the oxygen-free vacuum of space, but guns can shoot. Modern ammunition contains its own oxidizer, a chemical that will trigger the explosion of gunpowder, and thus the firing of a bullet, wherever you are in the universe. No atmospheric oxygen required.

The only difference between pulling the trigger on Earth and in space is the shape of the resulting smoke trail. In space, "it would be an expanding sphere of smoke from the tip of the barrel," said Peter Schultz an astronomer at Brown University who researches impact craters.

The possibility of gunfire in space allows for all kinds of absurd scenarios.

Imagine you're floating freely in the vacuum between galaxies — just you, your gun and a single bullet. You have two options. You either can spend all of eternity trying to figure out how you got there, or you can shoot the damn cosmos.

If you do the latter, Newton's third law dictates that the force exerted on the bullet will impart an equal and opposite force on the gun, and, because you're holding the gun, you. With very few intergalactic atoms against which to brace yourself, you'll start moving backward (not that you’d have any way of knowing). If the bullet leaves the gun barrel at 1,000 meters per second, you — because you're much more massive than it is — will head the other way at only a few centimeters per second.

Once shot, the bullet will keep going, quite literally, forever. "The bullet will never stop, because the universe is expanding faster than the bullet can catch up with any serious amount of mass" to slow it down, said Matija Cuk, an astronomer with joint appointments at Harvard University and the SETI Institute.

[Lee'sGhost]

Then you must be pointing the gun the wrong way.

[central_va]

I am not sure a percussion type primer would work in a vacuum.

[Atlas Sneezed]

The resulting smoke trail should resemble a large cone, not a sphere.

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Thank you. And the front of the cone might be spherical. The “sides” of the cone would likely flare outward. to a limited angle. And there’d initially be a “hole” in the center of the cone due to the bullet blocking the initial gases.

[Atlas Sneezed]

If you fire a 45 in space... the bullet takes off and travels at it’s rated ballistic speed forever. How fast will you travel the opposite way??

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About the same as if you were on earth and fired from a frictionless Radio Flyer wagon. In space, the most noticeable thing would be its causing you to rotate if the barrel axis was not in line with your center of mass.

[Atlas Sneezed]

I am not sure a percussion type primer would work in a vacuum.

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Why not? They work under water.

[TXnMA]

"I am not sure a percussion type primer would work in a vacuum."

Why would you think that?

Priming materials are made to detonate (not deflagrate [burn]) when mechanically crushed. Like black and smokeless powders,they contain a stoichiometric fraction of their own oxidizers, so they definitely do not depend on atmospheric air for reaction.

The only thing that might desensitize primers is the near absolute zero temperatures available in space. (The "Arrhenius relationship" dictates that reaction rates approximately halve with every 10K drop in temperature.) Even then, the instantaneous temperature spike generated by the crushing forces of the striker might well negate ambient temperatures.

I would be more concerned that those temperatures might degrade the deflagration rate of the propellant powder, rather than the sensitivity of the primer.

OTOH, what is most commonly used to effect separation of objects (rocket stages, etc...) in space? Explosive bolts... (But I understand that most of them are electrically initiated -- which could overcome any low temperature quenching effects...)

[Eye of Unk]

Space, the ultimate silencer. A snipers wet dream, no ballistics arc, no wind drifting or elevation, heat or humidity factors.

makes me kinda wonder if I were to shoot through a bottle thats been pumped down to a vacuum my shot would be totally silent?

[CodeToad]

Funny thing: The US signed on to the space treaty that bans weapons in space, so if you took a gun into space you would be violating US federal law.

[packrat01]

Aw, heck. 128 posts and nobody made claim to “havin’ the flattest shootin’ thutty-thutty this side of Betelgeuse”.

What’re FReepers coming to?

I’d make the claim, if I had a thutty-thutty.

[HiTech RedNeck]

Off topic, but did you actually spend the time to paste all these multifarious screen names together from everybody who posted something on this thread? Or is there some automated fashion to do that? When I say All, it just comes out on the list as All. And it does ping everybody who posted to that point, but I don’t get a list out of it.

Anyhow, “flattest shooting”? In outer space almost all the ballistic advantage of having a rifle would be gone, wouldn’t it?

[HiTech RedNeck]

A gun fitted with such a bottle wouldn’t bang (as loud), but it might make an awesome crash as the bullet pierced the bottle bottom.

[kanawa]

ping

[packrat01]

Yes. No, but I have text editing tools that help. Barring black holes, wormholes, dark matter, and the occasional photon; there would be SOME advantages that old technology has over new technology.

As long as space-time remains constant; that is...

[FreedomPoster]

There is no automated way that I know.

I’ve often thought I should figure out how to write a little thread parser that would extract that information. It shouldn’t be very hard.

[FreedomPoster]

Oh, and while the ballistics advantage would be gone, there would still be the optical and mechanical advantages. Longer sight radius, the ability to have higher velocity output from a longer barrel, and to be better able to hold the weapon steady for a shot, would all still be important advantages of a rifle over a pistol.

[jda]

Now you’ve done it - pointed out the one place where liberals don’t currently try to exert an influence, if not totalitarian rule. I’m sure, because you have let them know, that is even now in the process of changing. Thanks.

[jda]

...it is possible the bullet could hit you eventually

Not all that different from shooting a gun straight up into the air. I'm not sure why any sane person would do either.

[Eye of Unk]

I myself would wonder just indeed what would be the ideal caliber to carry if one was in space and needed a gun for protection, eventually the Pirates of Ganymede will try to board christian immigrant ships fleeing from Islam Earth so one could fantasize a wee bit.

Since its a vacuum velocity will not bleed off, you will need a penetrating type of projectile, a tracer would be ideal as when it makes contact with oxygen in you bad persons space suit it creates a mini thermobaric detonation and you now have bacon bits in a space suit.

However one cannot have just a singular pistol for space, no what we need is a smart gun, it should be talked to like in Lost in Space, it will be encoded to your personal DNA.
It should be able to instantly analyze the atmo and either send a super fast flechette such as in space, or a frangible low velocity round that won’t ventilate that goodly cocktail breathing soup of BO, WD40 and yesterdays spaghetti sauce from your tin can in space.

Or better yet a bullet so smart it will actually have a mini thruster motor so that when you get a million Moslems on the moon shooting into space with their AK7400 they won’t be turning a nearby space station into a colander.

[Eye of Unk]

In summary, in space you really should have a bullet that will stop either by timed flight, distance or destruction.

[HiTech RedNeck]

This is something that either perl or awk would make short work of. You still have to come up with a way of feeding what your browser sees (or shows) to the script.