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Fastest Spinning Black Hole Ever Found
brian0918 writes, "NewScientist reports that researchers in Cambridge have detected a black hole spinning at nearly 1,000 times per second — the fastest ever recorded. From the article: 'McClintock's team examined a black hole in our galaxy called GRS 1915+105, which lies about 36,000 light years away. They found the innermost stable orbit around GRS 1915 is so close that the black hole must be spinning at nearly 1000 times per second. The finding supports the idea that only fast-spinning stars can collapse to create powerful explosions called long gamma-ray bursts.'" The Astrophysical Journal abstract is open but you have to be a subscriber to read the full article there.
I thought this title was held by White House press secretary Tony Snow...
I'll form my OWN solar system! With blackjack! And hookers!
I would like to point out that "Long gamma ray bursts" would be an excellent name for a rock band.
The original article is from The Astrophysical Journal and I'm not sure if you can read this but I'll link it here. I have an account so that may be unreachable, if it is try the PDF of it or the abstract. I often enjoy reading the original article no matter how large and complex it is. If anything, it causes me to look up more terms so that I feel like I'm learning something.
My work here is dung.
I find it amazing that they can find an object which emits absolutely no light, halfway across the galaxy, and yet it's still so hard to find planets. I know they find the black holes by their accretion discs, but I still think it's remarkable.
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We know it won't fly apart from centrifugal force.
The simple truth is that interstellar distances will not fit into the human imagination
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The astrophysics arXiv preprint from June.
In theory, that could be a time machine... anyone know the details of the math?
PHEM - party like it's 1997-2003!
People, what we have is a model, not an observation. As TFA says, this model is based on assumptions, though fewer assumptions in the past:"Now, astronomers have measured the spin of a black hole with a new method that requires fewer assumptions."
The black hole may indeed be spinning at 1000 revs, or is might just be that one of the model assumptions is invalid.
Engineering is the art of compromise.
So the question is, whos grave is it and what did we do to get them to spin that fast?
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
...some astronomers have expressed doubt that stars would be spinning fast enough at this stage in their lives.
Now, i'm not an astrophysicist, but it seems to me that if a star had any spin at all before collapsing into a black hole, that spin would be magnified quite substantially, to conserve angular momentum (y'know, like a figure skater, or you spinning on your office chair).
The secret to creativity is knowing how to hide your sources. - Albert Einstein
If you'd like to see the whole article, as published in the Astrophysical Journal, you can find it on the astro-ph journal pre-print server. It's not the "official" journal version, but it should be identical to it (and was submitted to the preprint server by the authors).
I couldn't tell if you were experimenting with poor-man's cryogenics or looking for the orange sherbet.
Here's a 20 mile diameter pulsar spinning at 716 Hertz. When you factor in the increase in rotational speed with the black hole contraction, 1K sounds real plausible.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
Some astrophysicists say that some spinning cylindrical black holes warp spacetime enough that a projectile moving through its nearby region gets its velocity rotated to travel through time instead of a spatial axis. Is this new one the longest wormhole yet found?
--
make install -not war
one of the stock phrases, whenever you try to touch something interesting but non-functional in the game:
"Doooon't mess with it!"
In this case, it sounds extremely functional, in the gravity-that-rips-your-arms-off sense.
stuff |
Apparantly, there is no data loss. That idea has been revised. Just a very, very long access time.
Not that kind of Black Hole, you idiot!
I for one, welcome our new extremely dizzy overlords.
Yeah. Would you choose a neurosurgeon who pokes around people's brains in his spare time? I wouldn't.
If I remember correctly, centrifugal force as we know it actually reverses near a black hole. Pulling inward instead of outward. A rotating black hole may be compressed further by its rotation. Maybe someone familiar with the phenomena can shed more light.
The world is made by those who show up for the job.
A 747 could easily be deflected with BBs. The velocity and quantity of BBs is the most relevant factor. A billion BBs would deflect a 747 pretty easily. Or maybe just a handful of BBs at 2/3 the speed of light.
"A lot of research is focusing on creating an opening into the higher dimensional Hyperspace that contain innumerable universes. If it can be done, our whole world will change. We will leap forward in the advancement of science and technologies by millions of years.
Every black hole has a central singularity. These are points where mathematical modeling fails. That is because we assume every thing is 3-D. But the fact of the matter is these centers of black holes are singularities in 3-D but are actually simply transition points in higher dimensions..." [source]
Whoa
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That is true. However, this is currently our best estimate, and the theory applied is pretty well-respected. It may be interesting to know that this finding supports a 1997 suggestion that this particular black hole spins very close to its maximum. The 1997 paper attempted to explain in theory the x-ray jets this black hole emits by suggesting it spins. In contrast, this new paper actually documents an attempt to measure the spin.
Anyway, assuming the theory is correct, their method sounds pretty plausible to me (also assuming I'm understanding the paper and article right).
Basically, the size of a black hole event horizon depends mainly on its mass. However, if the black hole is spinning (most or all are believed to due to conservation of momentum), the event horizon contracts due to frame dragging.
Of course, we can't directly see the event horizon to measure it like we can measure the sun's radius. These black holes are far too distant to resolve. But, matter falling into the black hole is heated up due to friction. Just before it passes the event horizon, it gets so hot it emits x-rays that are detectable from earth.
The clever part is that the energy of the x-rays is correlated to the emitting particle's radius from the center of the black hole, since as particles spiral in further, they heat up more and more. So if you know the mass and can measure the highest frequency of the emissions, you can calculate the rate of spin. Of course, finding the mass and measuring those x-rays is not at all trivial, and the final step of calculating the spin probably took the 6 researchers who published the paper a year or so worth of work.
In General Relativity, gravity is the warping of space you refer to. The warp is the path light would take when travelling through that region. Everything with mass warps space-time a bit, and black holes do so a lot; so much so that any light you emit inside the event horizon bends around until it's in the singularity no matter where you aimed it initially.
Gravitons are a proposed quantum paritcle, and black holes and quantum physics haven't been reconciled yet. The warping-of-space-time explaination doesn't have the "why can gravitons get out" problem. I don't know what the quantum physics answer will be.
I have suffered from being misunderstood, but I would have suffered a hell of a lot more if I had been understood.