I’ve read that the crafts will last billions of years before succumbing to cosmic radiation. That’s a long time. Is it enough to allow them to exit our local galaxy (barring a collision, of course). Or would gravity keep them contained?
According to Wikipedia, escape velocity from the Milky Way is 550 km/s and the maximum velocity of Voyager was about 11 km/s, so it won’t escape from the Milky Way. Also, at that maximum velocity it would take about two billion years to go 100,000 light years, the approximate diameter of the Milky Way.
But aren’t we on the edge of the Milky Way? It wouldn’t have to travel the whole diameter, just get to the end.
No.
Well, Voyager inherits the Solar system’s velocity (assuming it’s going in the right direction!) which is about 220 km/s - but 220+11 still doesn’t do it.
On any timescale long enough to even consider leaving the Galaxy, it’s an n-body problem with a very large value of n. Under such circumstances, its velocity will be changed many times, and could well wind up escaping (or more descriptively, being ejected), even with an initial velocity that’s too low. Or contrariwise, an object with an initial velocity that’s high enough could still be re-captured before it got away.
Interesting. Given that illustration and leaving aside trajectory changes, where (approximately) would the Voyagers be in several million years? More towards the center or more towards the outer boundary?
OK, thanks. We are about halfway out from the center. So the full diameter of the galaxy isn’t what’s relevant. But, of course, it’s not like it’s it’s traveling straight out either.
How far are we from the “top” or “bottom” of the galaxy?
The initial direction of the two probes was deliberately made disparate. I doubt that even an approximation of the probable “orbit” of either of them was predicted for even one revolution around the center of the galaxy, but it would be only marginally different from the quarter billion years for the sun itself to make the trip. Micro meteor impacts over millions of years required for that one orbit would likely leave mostly a small cloud of fragments, and those not gravitationally bound in any way. The “position” of either of them would be entirely theoretical after one orbit.
Tris
Would the various velocity changes it experiences during its travel be (essentially) random? If so, wouldn’t that mean that there’d be a very low likelihood that any sequence of such changes would take it on a trajectory out of the Galaxy?
If it were that easy to leave the galaxy, there wouldn’t be a galaxy.
Survivor bias. Most of the matter that was originally part of the Galaxy (or any galaxy) eventually found its way into stable-ish captured orbits. Some didn’t, and got ejected. The only bits of matter we observe now are the ones that stayed captured.
Getting ejected would probably be harder for Voyager than it was for the original contents of the Galaxy, because it’s starting off in an orbit that’s very close to one known to be stable-ish. But it could still happen.
Ahhh, the “Samsung” theory.
In a million years, it will still be right next to the Sun, only about 40 light years away. However, its headed away from the galactic center. If left undisturbed, its orbit will take it a bit further away from the center than the Sun, then a bit closer to the center, then further, on so on.
Will the 2 Voyager spacecraft leave the Milky Way galaxy?
It will be picked up by a Federation Starship long before then.
Talks about the fate of the Voyagers.
In ~4 billion years, the Andromeda Galaxy will collide with the milky way; though most stars will not collide, some may be disrupted, torn from their orbits or ejected.
It’s possible that the Voyagers may be affected by other bodies before that, or by the andromeda galaxy, but it’s hard to predict.
In any case the Sun itself may swell up to a giant star before the Andromeda collision,and in any case will be moving between the different arms of the galaxy and oscillating above and below the plane.
For a pic.
So the Voyagers may wind up orbiting the Galaxy far after the Sun dies
Or, for that matter, is it moving away from the plane, out towards the viewer? The Milky Way galaxy is approximately 3,000 light years wide at our position. If we are in the middle then it would only have to travel 1,500 light years to leave.
About 41 million years traveling at 11 km/s, unless I’ve screwed up the maths. And that would depend on it traveling in the correct direction.
Of course, the real answer is that Voyager could never cross the energy barrier at the edge of the Galaxy.
The Sun bobs up and down relative to the center line of the Galaxy. The gravity of the Milky Way keeps it from getting too far away. Think of it as moving like a horse on a merry-go-round, up and down as it goes around, on a sinusoidal path. (Most other stars do the same, by the way.) The Voyagers don’t have enough additional velocity to escape this motion. They’ll bob up and down just like the Sun.
Yes, but it’ll come back much more powerful than it left, looking to get even or something.
What about the Milky Way’s own velocityrelative to external references? That’s 550 - 630 km/s. depending on frame of reference chosen.
I think it’s probably velocities all the way down…