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Astronomers Find Gas Cloud About To Fall Into Black Hole
First time accepted submitter pigrabbitbear writes "Black holes are basically celestial Cookie Monsters, gobbling anything and everything in sight. But because that appetite includes light itself, it's incredibly rare for us to actually see a black hole suck back an interstellar treat. Astronomers using the European Southern Observatory's Very Large Telescope have found just that: a mysterious, giant gas cloud that's rapidly been pulled into the maw of a supermassive black hole. The researchers, led by Reinhard Genzel of the Max-Planck Institute for Extraterrestrial Physics in Germany, discovered the cloud as part of a now 20-year ESO program tasked with tracking stars as they whirl around the supermassive black hole, known as Sgr A*, at the center of our galaxy."
To see this cosmic event happening before our eyes. I know that it has already happened and we are seeing the light from the event finally reaching our eyes or CCDS, but this is an awesome event to watch and shows how incredible the universe around us truly is.
It is humbling to think that it could be our solar system spiraling into the black hole, but we could save Earth if we had 6*6*6 levels of energy, we could keep Earth poised next to the black hole and watch everything else fall in. Until the Doctor opens the Satan pit that is...
liberare massarum ex ignorantia, clausa descendit molestie.
Really Slashdot? "Cookie Monsters"? "Interstellar treat"? Wow, I think I may have found a new low for a Slashdot summary.
Well, until tomorrow, anyways.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
Wouldn't that mean black holes aren't necessarily rare, but only that black holes near gas clouds are rare? There could be millions of them in the interstellar void, but with no gas to form an accretion disk, they would be completely invisible. And lensing effects would be incredibly difficult to detect. In fact, I thought that we only really detected most black holes if they were part of a binary system (which gives plenty of matter for x-ray radiation).
And, of course, it is absolutely impossible to see something that emits no radiation (ignoring the possibility of Hawking radiation, which is too weak to see in most cases anyways), so technically black holes aren't hard to see: they are impossible to see. We can only infer it's presence through the effect it has on matter outside the black hole itself. The x-ray radiation is not technically from the black hole itself, but rather from the effect that it's gravitational field has on incoming matter.
I'm not an astrophysicist... but I'm working on changing that.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
So what does "about to" mean in astronomical terms? Tomorrow? Next year? In a few million years?
Roughly two years: http://www.scientificamerican.com/article.cfm?id=black-hole-gas-blob
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... because most black holes are formed from the remains of particularly large stars, and such stars are formed from the gravitational collapse of large gas and dust clouds, one would expect most black holes to be close to regions where lots of stellar formation has taken place. Such places would quite likely still have lots of gas around.
However a black hole could have formed early in the history of the Universe. It is thought that if there are any really small black holes, they are left over from the Big Bang. Those black holes could indeed be in places where we could not detect them, and because they are not very massive, we could not see their effects on nearby matter.
It is the very small black holes that emit lots of Hawking radiation. The intensity of it increases with the gradient of the gravitational field. Large block holes have a less steep gradiant, smaller holes a steeper one. Very small black holes may have formed early in the history of the Universe, but by now would have evaporated due to emitting all that Hawking radiation.
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I seem to remember back in my university days (its been a little while) studying that their was an inverse relationship between the size of a black hole the temporal and gravitational effects at the event horizon. In effect, if the black hole was massive enough (million of stars), it could be theoretically possible to cross the event horizon with my atomic structure intact. I always imagined what a fate it would be to fall into such a monster and watch eternity pass before my eyes. I am not an astronomer, however, so my memory on this matter could be faulty.