If you shot a bullet in outer space, would it travel forever?

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tamaneko

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Since there is no friction or air resistance in outer space, does that mean that if you fire a bullet in outer space, it will just keep on travelling indefinitely as long as it doesn't hit anything else out there in the vacuum or get caught up in the gravity of a star?
 
Space isn't a complete vacumm, so the projectile would eventually stop.
If fired within the Solar System, it would probably be captured by the gravity of the sun or one of the planets.

Outside the Solar System, it might travel for years...
 
The escape velocity of the solar system is over 138,000 fps (42.1 km/s), so the bullet is not leaving the solar system. It would actually not be moving very fast in spatial terms. To escape earth entirely, you would have to be moving at 1.2 km/s. Since bullets travel at about 1 km/s, you are not gonna go for long.

you would travel the other direction for a while

In space, you could pick up more speed by spraying an air hose connected to a tank of air than you could by firing a bullet. Even though you are "weightless" you still have inertia and still have the same mass.
 
Even if given escape velocity from the solar syatem, gravitational attraction would cause it to impact something eventually. I am not a scientist/astronomer, nor do I play one on TV.
:)
 
Most likely, it would eventually fall within the gravitational pull of some star. However, you asked a theoretical question, so here goes.

If there were truly no friction, and ifit were fired from a spot where it was not significantly affected by any gravitational fields, and ifit were fired in a direction where it would never enter any gravitational fields, then yes, it would travel forever.
 
No, the real question is would you be breaking any local ordinances on discharging a firearm.
 
Divemedic you missed a digit, initial vertical escape velocity from Earth is not 1.2 km/s but 11.2 km/s.

This does decrease as you reach greater altitude so if you were already in orbit at say 9,000 km the vertical escape velocity is down to a mere 7.1 km/s

If fired from orbit, unless you reach the escape velocity all that will happen is you will boost to a higher or lower orbit, depending on which direction you fire in (increasing or decreasing your current orbital velocity).

Theoretically, and assuming you were firing from and using various of of the (relatively) neutral gravitational points (Lagrange points) and using multiple planetary gravitational slingshots you could eventually reach solar escape velocity. It is however unlikely the bullet would survive passing through the Heliopause and solar bow shock.

http://en.wikipedia.org/wiki/Interplanetary_Transport_Network
 
The real question is if you fired a mini-14 in outer space would the ejected brass travel forever? I believe it would.
 
It would stay in motion until something stopped it. Whatever that is who knows.

At least that's what a guy called Isaac Newton said. I think he has a website...
 
it would stay in motion until captured by the gravitational field of another object. That object could be a planet, moon, star, meteor, or any other cosmic debris.... until such a thing took place, it would stay in motion indefinitely.

the question was not whether or not you would be able to break the atmosphere or get out of the solar system... only what would happen.. if it did nothing but circle the solar system as many objects do, it would still remain in constant motion.
 
Does anyone else remember the longest golf drive in history? (yes this is on topic) :) Kinda,,, Sorta.....


I am sorry to say I forget which astranaut did it. :( but he did a drive on the moon. It did NOT escape the gravity of the moon but went for a LONG ways. (miles and miles)
 
I am sorry to say I forget which astranaut did it. but he did a drive on the moon. It did NOT escape the gravity of the moon but went for a LONG ways. (miles and miles)

If you shot a bullet in outer space

good point but the golf ball was being driven from a large mass with a gravitational pull.. if you were free from such a mass... IE OUTER SPACE... there would be no gravity to restrict its movement... until it strayed close enough to one such item and was pulled to its surface...
 
I have heard that some astronauts carry a .45 in case they have to hurry back to the ship on a space walk while they are a long distance away, the recoil will push them back pretty fast. Have also heard the projectile stays in place and the gun/astronaut goes back. Personally it is not really something I think is true but "I have heard" it.
 
"Does anyone else remember the longest golf drive in history? ... I forget which astranaut did it."

It was Alan Shepherd. He was an avid golfer as well as an astronaut. IIRC, he took a shortened shaft 5 iron. I doubt the ball went miles and miles. On earth he would have been lucky to get 100 yards out of the shot due to the club he used and the space suit hendering his swing. Maybe he got 600 to 700 yards out of it, but if it hit rock on the way down, he probably got some good distance from the bounce.

For the bullet in space question, it's been answered well. Even in intergalactic space (the emptiest space there is), there are several atoms per cubic meter (usually hydrogen). It would go a long, long distance - many light years distance probably, and many millions of actual years, but it would eventually stop. However, even the term "stop" is relative in space. Stopped in relation to what? Even before the bullet was fired it was traveling at a tremendous speed relative to the sun, for example.
 
What about "every action has and equal and opposite reaction"? The shooter, even tho of more mass the than the firearm, would still be "moved" from recoil.

Wouldn't the firearm have to anchored to something of substantial mass in order to get full velocity and not lose some in the initial firing?
 
Nothing ever "stops" in space. If you fired the bullet anywhere near the solar system it would take up an orbit around the sun, a planet or moon.

Assuming you were far enough from the sun or any star to achieve escape velocity the bullet would wind up in orbit around the galaxy. Outside the galaxy it would orbit the center of mass of the "local group." There's always something out there to orbit.

Anyway, "stop" really has no meaning. The bullet sitting on your dresser may be at rest in relation to you, the dresser and the Earth but the entire bullet-Earth-tamaneko system is spinning at hundreds of MPH, and circling the sun even faster.

So it will never "stop."
 
I'm pleasantly surprised no one has brought up the erroneous "there's no air in space so the powder wouldn't burn" objection yet, because someone usually does.

Yes, if the bullet was fired in space it would travel at muzzle velocity until it hit something or ran into a gravity source. If it were fired while in orbit it would be subject to orbital mechanics, but in orbit is a very special case. Most of space is a vast emptiness and while the bullet might eventually hit something, in all likelihood it would travel at its original velocity for a long time. If you are going to wait for the friction caused by space being an imperfect vacuum to slow it down, then you'll be waiting for a very long time.
 
Does anyone else remember the longest golf drive in history? (yes this is on topic) Kinda,,, Sorta.....

I do, on Earth anyway, I believe it was in the early 70's by a professional gambler. The bet was that he could drive a golf ball for a mile. He went up to Lake Erie in the middle of winter while most of Erie was frozen over. They never did find the ball and he won the bet.
Ok, now back on topic. Yes bullets require oxygen, It was proven when they had to fire "Vera" through a space suit during one of the "Fire Fly" episodes. :D:D:D:D:D:D:D
 
Wouldn't the firearm have to anchored to something of substantial mass in order to get full velocity and not lose some in the initial firing?
No more so than on earth. It's the mass that counts, not the gravity acting on that mass. You would be hard pressed to measure any difference in muzzle velocity on earth vs in space using a conventional chronograph (assuming you can measure it before it went any appreciable distance in air). A big difference, of course, is that the muzzle velocity would remain fairly constant in space no matter how far away from the muzzle you were.
 
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