what happens if you fire a gun in space, not to you but to the bullet as long as there is nothing in the way?

Question

as long as there are no planets, stars or moons in the way, what takes place if you fire a gun in space?

Answer 1

The answers above are mostly accurate. Assuming there is an explosion in the chamber (which would require oxygen), the bullet will travel at muzzle velocity indefinitely. Assuming it hits no stray atoms of interstellar gas, and isn't pulled into a stellar or planetary gravitational field, it will continue on until the end of time.

However! It will not go in a straight line. It will gradually curve through the universe, until someday it completes a great circle. During these trillions of years it has been travelling, the universe will have expanded, so it will not end up exactly where it started, but a bit further out. And if it goes on, around and around, it will ultimately perform an outward spiral.

The universal rule here is that any phenomenon will, if uninterrrupted by another phenomenon, become a cycle (circle/spiral). This rule applies to biological systems, bicycle wheels, economic cycles, seasons, automotive engines, etc.

That is all theoretical, of course. Realistically, the bullet will end up being drawn into orbit around a star, and eventually spiral down into it, where it will be melted down into heavy atoms, and, when the star goes supernova, be scattered across its galaxy, later coalescing into a new star, with planets, where life evolves, and guns are invented, etc... a cycle.

Answer 2

The answer mentioning inertia has it all wrong. Inertia is the property that an object at rest tends to stay at rest. Once the gun is fired, inertia is overcome pretty darn quickly.

To answer your question. In a perfect vacuum of space, it would continue at its original rate pretty much forever. However, space is not a vacuum, so bit of cosmic dust will get in the way, each bit slowing the bullet down as it goes. Also, even if no planets or suns are directly in the way, each object exerts a gravitational influence, bending the bullet's path and eventually slowing it down, probably to be captured by some interstellar object. Sooner or later it will fall on something, meaning it will hit something.

The guy worrying about the lack of oxygen preventing the gun from firing also got it wrong. All the combustion of the bullet firing takes place in the shell. The expanding gasses in the shell (from the gunpowder going off) is what pushes the bullet out of the gun.

Answer 3

I would expect that the bullet's forward movement would continue on the same plane as it was when it was fired from the gun.

But at some point, I wonder whether the bullet would be affected by the gravitational pull of a planet, star, or moon. It's movement may then be altered to an circular or elliptical orbit, such as we observe with comets.

Considering mass, at some point the bullet may become a "moon". Unless of course it were to be destroyed by entering the atmosphere.

experts.about.com/q/Physics-1358/asteroids.htm

curious.astro.cornell.edu/question.php?number

www.absolutewrite.com/forums/showthread.php?p=348478

Answer 4

The bullet will slow, but it will slow very slowly. If muzzle velocity is 2000fps then perhaps the bullet will be traveling 1999.9999 fps 1 million years later. Wikopedia states that space contains "a few hydrogen atoms per cubic centimeter at 10−14 pascal." The chance of hitting even one atom per million years is probably negligible. And the effect of any nearby stars' solar wind would probably have even less of an effect than the bullets off-chance collision with hydrogen atoms.

Answer 5

Well, space isn't entirely empty so the bullet would meet resistance that would eventually slow it down. However, it might take a million years for it to do so. Until then it would just go in a straight line unless it ran into something.

Answer 6

depending on the type of gun you shoot you will have some type of kick back that will send you backwards while the bullet you shot from the gun will keep going straight unless it's affected by an unbalanced/outside force such as a planet's gravitational field, astroid, moon, whatever..........well if you knew Newton's 3 laws of motion you would not need us to answer this question for you.

Answer 7

As long as there's nothing in the way, the bullet will never hit anything.

Answer 8

You must be expecting the answer, hinting that there are no planets, stars or moons.... it will just keep going and going forever.

Answer 9

As long as it doesn't hit anything, and no gravitational pull affects it, it would keep going in a straight line forever, with no loss of velocity.

Answer 10

It keeps going and going and going and going.....

There would be no resistance but there would be a certain amount of inertia, and eventually it would slow down and just drift in the solar winds (assuming there were any).