chronobreak said:
Haven't we known there was a black hole at the center of the universe for a long time?
Yeah, astronomers have known about the black hole at the center of our "galaxy" for a while. They theorized one was there long before it's discovery.
xitel said:
Um, the Milky Way is huge. It's not that it's going to suck everything in, but the gravity well it creates is what's keeping the galaxy together.
Yes and no. It's gravitational pull only truly affects the stars closet to the center. In truth, it's the shear size and mass of our galaxy that holds it together. Some astronomers have even theorized that the black hole at the center of our galaxy didn't form our galaxy, but that it may have formed in an outer spiral arm and "sunk" to the center, gaining mass along the way.
implodingMan said:
We already knew it was there. This just confirming its existence. Also, just because it is a black hole does not mean matter will instantly rush into it (as it obviously isn't doing right now). If you replaced the sun with a black hole of the same mass them the Earth would continue on its merry way. We would all still be killed, but that would be from the freezing temperatures and lack of light.
Not really. Replacing our sun with that black hole would indeed cause us to be pulled in. It wouldn't be instantaneous, but the planet would progressively accelerate faster and faster as it approached the event horizon. However, do to the shear size of the black hole, we wouldn't "spaghettify" until we passed within the event horizon. However, when it starts (assuming we're not dead from the x-ray radiation) it would be extremely painful. You're basically being exposed to higher and higher magnitudes of gravity.
Dayne Gonsalves said:
It's probably million of light years away, and was probably there since the beginning of time, so i wouldn't worry. Yet.
Actually, it's about 40,000 to 45,000 light years away, I believe. Our solar system is located near the outer edge of the galaxy, on one of it's spiral arms. With our galaxy being roughly 100,000 light years across, only makes sense.
RedDiablo said:
I'm pretty sure that a black hole doesn't move, and that we are probably far away from it. Also, there are probably hundreds of black holes around the Milky Way, seeing as it is a pretty big galaxy. And in fact, the center of the Milky Way is a black hole.
Actually, they move just like everything else. They're not some mystical phenomenon, they're just giant stars whose nuclear reaction died out and collapsed under their own gravity into a singularity. Ergo, if the star it formed from was moving, the black hole would be moving. Also, there are actually millions upon millions of black holes just within our galaxy, not including ones just outside our galaxy, in the smaller galaxies orbiting our galaxy, and the rest of the universe.
TGLT said:
Don't worry, if we manage to get out of the system before the star eats the planet we'll probably survive long enough to die of universal heat death. Or our galaxy crashing into another.
True. Long before we need to worry about falling into the black hole at the center of the Milky Way, we'll either fall into a smaller, solar-mass black hole or have a run-in with a pulsar. Our solar system is moving constantly through the galaxy, both orbiting the center and oscillating up and down through one of the spiral arms. In fact, it seems that every time our planet has passed through said spiral arm, there's been a mass-extinction event. Coincidence? You're also right about the galaxy collisions. Our closest neighboring galaxy (of significant mass) is Andromeda, which is twice the size of ours. As we speak, it's on a collision course with ours. It's a long time out, but it will end in either of two outcomes. Our solar system will either be tossed out of both galaxies and into empty space or will be flung into the core, where the two galaxies super-massive black holes will be merging. Of course, these events are on such long time scales, we'll be able to find a way to avoid them, or go extinct. However, there's something we can't avoid. It's called the Big Rip. http://en.wikipedia.org/wiki/Big_Rip Basically, the mysterious energy physicists have been observing the effects of for years, known as dark energy, may very well one day rip everything in the universe apart. Dark energy's repulsive force, known as the cosmological constant, is pushing all matter in the universe farther and farther apart. It's already out-classed gravity on large scales, which is why all the galaxies in the universe are expanding away from each other at an increasing rate. Some have theorized that there may come a day where dark energy's repulsive force will exceed local gravity and even the strong and weak nuclear forces that hold atoms together. Meaning, the universe is doomed to dissolve away into total darkness. Kinda gloomy, huh? Think I've said enough about "dooms day" scenarios.
