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

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Just to put things in perspective, space is a HUGE emptiness, sprinkled very, very lightly with stars. The nearest star to our sun, Proxima Centuri, is 4.3 light years away. That's 5.88 trillion miles away. If you fired a pistol bullet in space it would take just under a million years to cover the distance. That's assuming you fired with the proper swing and lead, of course. ;)

So with trillions of miles between stars, it would be easy for a bullet to travel for eons without coming within sniffing distance of anything. The odds of running into something are literally astronomical.
 
evan price said:
I guess the REAL question is, what if you were travelling .999999 of the speed of light, and then fired that gun in your direction of travel. What would happen?
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Are you thinking, perhaps, the bullet will reach 1.000001 lightspeed, or c?
It won't. Thou shall not add one's own speed to that of a projectile when discussing Quantum light physics.

Astronomer Carl Sagan actually came up with a thought experiment to show this:
A bicyclist is riding along a road in a direction pretty much straight toward an observer. On a side road perpendicular to the path of the cyclist, a truck comes along, and unfortunatly, collides with the cyclist. The observer witnesses the collision exactly as it appears from his point in reality.
IF it were proper to add one's speed to lightspeed, the light from the cyclist would arrive at the observer first and he'd see the cyclist tumble off and get mauled, then the truck would arrive at the collision point.
BUT, we all know we don't see things like that!​

So unfortunatly, even if you could travel .999999 c nothing you did could propel the bullet faster than light itself. BTW, at that speed, your mass would have become incredible! Mass actually increases as you approach lightspeed.
 
So unfortunatly, even if you could travel .999999 c nothing you did could propel the bullet faster than light itself. BTW, at that speed, your mass would have become incredible! Mass actually increases as you approach lightspeed.
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Your mass as perceived by an outside observer. You would see yourself as having normal mass, and your stationary surroundings affected by Lorentz transformations.

Lorentz gamma for a speed of .999999 c (983,570,073 ft/sec, I heard J.D. Jones has a wildcat .17 that approaches that speed :D) is a little over 700, meaning your mass as perceived by an outside observer would just over 700 times normal.

FWIW, a 55-grain .223 bullet at .999999 c would have a muzzle energy of 118,124,382,940,567 ft-lb or 38.25 kilotons of TNT (160,155 GJ), which is between two and three times the energy of the Hiroshima bomb.

And to address the OP, if you were able to travel out into intergalactic space before shooting the gun, and aimed it away from any superclusters in the line of sight, it would probably never hit anything, ever, due to continued expansion of the universe over the time scales involved.
 
Since this is a silly thread - let me hijack by adding something about the movement of the galaxies, etc.

Ever wonder about time machines - if you went back 100 years, just in time - you would be floating in space. Oops. I once read a story about that. The time dude popped out in space but had enough sense to hit the return button before dying.
 
Can I add a little different question
If it is about 23,000 miles around the earth and we travel that far in 24 hours.
We are really going 958.3 miles an hour. A catagory 5 tornado only reaches about 350 miles an hour. Why don't we have 958.3 mph winds. So how many feet per second is a bullet really going if you shoot it to the east at 3,000 FPS?
 
natman - you need to recalibrate your calculator. :)

It is roughly 25 trillion miles to Proxima Centauri. Even if an object could escape the sun's gravity (a bullet ain't gonna do it), it still needs to navigate through the Kuiper belts and Oort clouds of both stars, and there's a lot of trash and garbage in there to deflect it.
 
I wonder if you would get a limp wrist effect?
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Only if the shooter was from San Francisco
FWIW, a 55-grain .223 bullet at .999999 c would have a muzzle energy of 118,124,382,940,567 ft-lb or 38.25 kilotons of TNT (160,155 GJ), which is between two and three times the energy of the Hiroshima bomb.
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Think what that would do to a prairie dog
 
a 55-grain .223 bullet at .999999 c would have a muzzle energy of 118,124,382,940,567 ft-lb or 38.25 kilotons of TNT (160,155 GJ), which is between two and three times the energy of the Hiroshima bomb.

Think what that would do to a prairie dog

using them numbers it would blow a guys head plum off if you just spit in his face
would Obama out law water so you couldn't spit
 
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All this talk about space and nobody mentioned the wormhole? All you have to do find a wormhole in space fire into that and the bullet will come out some other place in outer space, everybody knows that. :rolleyes:
 
benEzra said:
Your mass as perceived by an outside observer. You would see yourself as having normal mass, and your stationary surroundings affected by Lorentz transformations.
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Yes of course, that's why it's RELATIVE.(Theory of relativity). But you'd still have an ever-increasingly difficult time accelerating the closer you get to lightspeed.:rolleyes:
 
I actually did this with a 22lr 80 trillion years ago; the bullet is still going. If you pm me, I'll give you an update every million years or so.
 
natman - you need to recalibrate your calculator.

It is roughly 25 trillion miles to Proxima Centauri. Even if an object could escape the sun's gravity (a bullet ain't gonna do it), it still needs to navigate through the Kuiper belts and Oort clouds of both stars, and there's a lot of trash and garbage in there to deflect it.
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Good catch. 5.88 trillion miles is one light year, not the 4.3 light years to Proxima Centauri. So it would take about four million years to cover the distance, not one.

Yes, a bullet would not escape the sun's gravity. The point I was trying to make is just how vast space is by showing how long it would take to cover the distance involved, not that you could actually shoot a pistol from the solar system to Proxima Centuri.
 
If you managed to exceed the speed of light and then fired the bullet...It would, inevitably, travel backward in time and kill your grandfather. The temporal paradox would cause the entire universe to cease existence. You would then become the greatest mass murderer ever.
 
But you'd still have an ever-increasingly difficult time accelerating the closer you get to lightspeed.
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Not from your own perspective; again, only from the perspective of an outside observer. If you started out accelerating at, say 10 m/s^2, you would continue to measure yourself accelerating at a constant 10 m/s^2 no matter how close you were to the speed of light. If you fired a .223 in the direction you were traveling while going .999999c, you'd chronograph the bullet at ~3100 ft/sec just as if you were at rest.

What would be happening from the perspective of an outside observer, though, is that your seconds would be getting progressively longer, and your meters would be getting progressively shorter. So you are still measuring an acceleration of 10 m/s^2 and your gun's muzzle velocity still chrony's 3100 ft/s, BUT it takes nearly 12 minutes (from the at-rest observer's perspective) for your stopwatch to tick each of those seconds, and your meter stick is only 1.4mm long from the observer's perspective. And the closer you get to c, the longer each second takes and the shorter the meter stick gets, as seen from the outside. But you'd see/feel nothing out of the ordinary as long as you didn't look out the window, and nothing in your ship would be foreshortened or running slow as seen by you.
 
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Okay okay ... I'm getting conflicting reports ...James Kirk says one thing and Steve Zodiac another.:eek: This whole relativity thing always boffled me ... it's amazing someone (Einstein) could think of this who couldn't even figure out how to use a comb!!!!!!:neener::neener:

:eek::eek:​
 
Okay okay ... I'm getting conflicting reports ...James Kirk says one thing and Steve Zodiac another. This whole relativity thing always boffled me ... it's amazing someone (Einstein) could think of this who couldn't even figure out how to use a comb!!!!!!
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LOL. And the rabbit hole gets deeper than that, once you get into quantum physics. If you put two particles into an entangled quantum state, send one of them halfway across the universe, and then measure the quantum state of the local one, the quantum state of the one halfway across the universe changes instantly with no time delay. And if a barrier is sufficiently thin, a particle can exist on both sides of the barrier at the same time, or pop from one side of the barrier to the other without physically penetrating it....

I think maybe God made physics to keep us humble. :D
 
The real question is if you fired a mini-14 in outer space would the ejected brass travel forever
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No the question is if you fired a mini 14 in outer space would you have a better chance of hitting what you aim at than here on earth.:neener:
 
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