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Black Hole Observed by X-Ray Satellite
eldavojohn writes "Scientists at JAXA and NASA used the Japanese Suzaku satellite to collect data and observations at a distance nearer to a black hole than we've ever been. From the article: 'The observations include clocking the speed of a black hole's spin rate and measuring the angle at which matter pours into the void, as well as evidence for a wall of X-ray light pulled back and flattened by gravity. The findings rely on a special feature in the light emitted close to the black hole, called the "broad iron K line," once doubted by some scientists because of poor resolution in earlier observations, now unambiguously revealed as a true measure of a black hole's crushing gravitational force.' Suzaku also has been providing images and data of super novas and their activities. It's always nice to see national space agencies working together, it almost gives me hope that the world might one day be united in space exploration."
"Nothing for you to see here. Move along."
The grass is always greener on the other side of the light cone.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
I'm impressed, they see something coming out of it. I thought we observed black holes by what they did to matter and space (bending light) and radiation emissions.
Exactly how much closer is this black hole and do we need to start worrying about it, now...
A feeling of having made the same mistake before: Deja Foobar
It's a place to start. Every nation has scientists that are specialists in their own field, if we can get together and share information about space, imagine the possibilities.
That which does not kill me only postpones the inevitable.
I have never found a really good explanation for this: How do we know a blackhole truly has an infinite density, and not just so incredibly dense that it, in fact, has a stronger gravity than even light can escape? My mind has a difficult time with something becoming infinitely small. I can understand it becoming so tight that there is no space between the smallest particles, but cannot fathom something smaller than that.
Can anyone help me out here?
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
Then isn't it just a star in a different frequency?
Could we consider our own sun a Yellow hole since we cannot see into the middle of it?
liqbase
Holly: Well, the thing about a black hole - it's main distinguishing feature - is it's black. And the thing about space, the colour of space, your basic space colour, is black. So how are you supposed to see them?
not only is that why they didnt notice it, but confirms exactly what parent is saying.
Why does no-one ever discover giant kittens at the centre of galaxies? Or that dark matter is made out of candyfloss? I need more comforting science, dammit!
Given that the black hole is a few zillion light-years from earth, I don't think that this satellite is much closer to it than anything ground-based. But the satellite has a much clearer view of the black hole (or at least, of its event horizon) without the atmosphere in the way, and that's what the press release means by "closer to the edge".
In case you're interested in what the K-Iron broad line is check out http://arxiv.org/abs/astro-ph/0212065 and http://web.mit.edu/newsoffice/2005/spacetime.html
Giant kittens are comforting?
The MCG -6-30-15 paper referred to in the press release. I don't think the MCG -5-23-16 paper has been made public yet.
The most interesting thing about the paper is that Suzaku's Hard X-ray Detector (which operates in a comparatively poorly studied waveband) is consistent (based on the model of an accretion disc around a spinning black hole) with what's happening in the softer X-ray band.
Slashdot - Mutual Assured Discussion
A black hole is not a literal physical singularity. There are "bigger" ones and "smaller" ones. It is instead a mathematical singularity: it can be treated as a point object in the sense that if you lay out a gravitational grid across the universe, each black hole is a point, a hole on that grid where nothing comes out.
So why do black holes emit X-rays and Hawking radiation or why do they emit stuff at all?
The black holes don't emit anything per se. However, as particles close to the event horizon are accelerated more and more by the gravitational pull of a black hole, THEY can emit radiation. An illustrative model is a star/black hole binary system in which gases from the star are being pulled in to the black hole, thus emitting X-rays as they are accelerated.
Hawking radiation is also not really emitted from the black hole itself. Theory goes quantum fluctuations occur so close to the event horizon that one particle gets sucked in while the other escapes: imagine a positron-electron pair appearing right on the cusp of an event horizon. Let's say the positron disappears into the black hole while the electron escapes out into the universe. From our perspective, the electron will have been "emitted" from the black hole. The energy required for this is also taken from the black hole as the positron (think of it as negative energy) will go into the black hole and take that much energy away from it.
"The Cube": it just wouldn't be the same without fellatio "Corey Kosak": It just wouldn't be the same... oh, looks like
they invented the Sudoku satellite. But what does that have to do with black holes?
How much closer to the black hole can this satellite really be? Isn't this a bit like asking Shaq to describe the moon to us because when he stands up, he's a foot closer?
International cooperation is easy when no one sees a profit in the near future. But if someday comes where we're competing for resources in space, say bye-bye to cooperation.
"Convictions are more dangerous enemies of truth than lies."
Wrong branch of science. You might try a major pharmaceutical company or your local drug dealer instead.
I Am My Own Worst Enemy
More bullshit whiney rhetoric from the left.
What in that sentence gave you the impression that the author even supports high taxation of the rich to fund comprehensive public services, let alone workers' control of the means of production?
At any rate, you seem to have overlooked the word 'always' in the sentence, which strongly implies the existence of other cases of international cooperation in space. Such cooperation is always nice to see. Or perhaps you think it's a bad idea?
Real Daleks don't climb stairs - they level the building.
So my question... can I use my gravity gun to hurtle the star so the black hole follows the star?
but wait... there is no gravity gun... WTF are we to do now? Call Dr Freeman!
"Don't Forget to Salt the Fries"
Personally thats scary as hell! I mean, cats just look at you and you know what they're thinking "If you were smaller, you'd be lunch". Now...giant kittens, we'd be lunch if they ever attacked.
But is it supermassive?
"Why do drive-thru ATMs have Braille keypads?"
Because it's cheaper for a manufacturer to make only one line of keypads that have Braille, and the ATM manufacturers know it's cheaper to use those mass-produced Braille-capable keypads than to have a company manufacture Braille-less ones.
:(){
Your arguments were wrong the first time you posted them, as you would know if you read the responses to them.
I will repost my response:
The black hole will not form in any finite time since time there just stopped!
This is wrong. There is a finite set of events at which the horizon forms; we can just never see it form. See this FAQ.
For the observer falling towards the "hole", time in the rest of the universe just speeds up. In a matter of minutes the universe will age billions of years,
This is also wrong. A similar misconception is described in this FAQ.
Yes, I know many scientists disagree with me. Just think for yourself for a minute.
Ah, the old "if you disagree with my crackpot theory you must be a closed-minded conformist" argument.
Have you ever bothered to investigate whey "many scientists disagree with you"?
The basic principle is that things are spinning. In the case of a galaxy, the whole thing would originally have formed from a collapsing gas cloud. This cloud would have had some small overall spin, which would be magnified during collapse by conservation of angular momentum (try it yourself: hold a brick in each hand, spin around and around as fast as you can with your arms outstretched, then quickly pull in your arms and hold the bricks to your chest...) So you've now got a smaller ball of gas which is spinning quite fast. Now it should be obvious how it flattens out: the spin stretches it at the equator, gravity collapses it at the poles, and before long you've got a disc.
As for black holes, that's spin again, but it works a little differently. Black holes are so powerful that they drag space itself around with them, and infalling matter really has no choice but to fall in line over the equator...
Real Daleks don't climb stairs - they level the building.
it almost gives me hope that the world might one day be united in space exploration
I guess you missed yesterday's story documenting the US' clear intention to be the single entity with control over access to space; 'The policy calls upon the Secretary of Defense to "develop capabilities, plans, and options to ensure freedom of action in space, and, if directed, deny such freedom of action to adversaries."'
Is that black hole near to Milky Way Galaxy? I wonder how many on these black holes last for a longer period of time as most of them collapse under their own massive gravitational force
http://en.wikipedia.org/wiki/Black_hole
Someone better hurry. This is a fast-developing situation, and no one knows what'll happen to the article when the MECO people get their hands on it.
Q: What did the comedian say to the crowd?
A: If I knew, this joke would be funny.
You are pretty warm. I'll try to fill in the blanks: if you were the hypothetical astronaut descending towards the event horizon, electromagnetic radiation emitted further up the gravity well would be blue shifted. The wavelength would be compressed - as you cross the event horizon, infinitely so, because as you say, time is frozen within the black hole. Outside of the black hole, the opposite is true: radiation from within the event horizon is infinitely red shifted. It never reaches you.
You seem to be heading towards the argument that because time is meaningless within the event horizon, sufficient matter would never *quite* manage to accrete and generate a black hole. Well, not so much. As you approach the event horizon, electromagnetic radiation that you emit and perceive to be of 400nm wavelength would be to an outside observer perhaps 500nm, eventually 1cm, 100m, 100km, 1 light year, 10^100 light years, 10^1000000 light years.... How would anyone detect such weak radiation? They can't, because you rapidly stop transmitting information that is at all perceptible.
The same phenomenon occurs as matter collapses into a black hole. It's density increases, increases and increases with its red shift, and wink; it's gone. One moment, you are receiving gamma rays, the next only xrays, then visible light, then radio waves and then, finally, you would need an antenna so long that you would not be able to distinguish emanations from the black hole from background radiation and noise in your instruments.
I can see why water flowing out of a sink would have a disk shaped surface, but not really why black holes or even galaxies should.
Because of centrifugal force. As the material orbits the object at high speeds, it is thrown outwards perpendicular to its direction of travel. Like cooking a pizza, where the chef takes a sphere of dough and spins it around on his finger to make it flatten out into a pie.
They're yellow holes.
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Serious question. Any speculation as to what would happen should two black holes get caught in each other's event horizons?
It must have been something you assimilated. . . .
Uniting exploration (or anything else for that matter) does not necessarly yield better results.
I would like to convince you of this. First to rephrase, the black hole is an aspmptotic limit when to goes to infinity.
A clock is falling towards a "future" black hole. The clock stops its fall (Or we compensate for his speed in our calculations) and compares its time with that of a our distant clock.
As the gravitional field increases he will see that:
(1) t*=t[1-(2GM)/(rc^2)]
Oviously, when
(2) r=2GM/c^2 => t*=0 (This is of course a limit expression, but you get my point)
I will use the phrase event horizon to refer to the surface that will form the evetnhorizon when time asymtotically -> infinity.
This r, is the event horizon or Schwarzschild radius. (To simplify the math, we assume that the hole in non-rotating. If it rotated, the equations gets messy. Including that the event horizon will differ from the Schwarzschild radius. This however will not reduce the univesality of the argument)
So for the external observer, as the clock falls toward the black hole, it will slow down, and as it approaches the event horizon, it will slow down, and effectively "freeze".
The future event horizon will be a graveyard littered with debris frozen in time. The debris and our clock will asymtotically approach the event horizon as t-> infinity.
Now, we all agree on this bascic theory.
Now my claim is that because of the above observation, a black hole can not form in any finite time.
It does not take any math to think through this. If the hole is already there, fine, but think of a region of space asymtotically close to becoming a black hole as it absorbes mass. The time dilatation approches infinity *before* the black hole forms.
This effectively stops the black hole from forming in any finite time for the distant observer.
Of course, as distant observers looking at small and medium black holes, the distinction I am making is not very relevant. You will see enourmous radiation as matter spirals toward the event horizon, indicating the violent gravity and tidal forces. There will be little difference in the observation.
With a truly massive blck hole the difference would be distingisuable. Ther ewould of course be no singularity inside, and the mass distribution would be asymtotically like it was before the region got close to forming a black hole.
So:
1. This is experimentally verifiable
2. Conforming to general relativity
don't cut it off www.mgmbill.org
Anyway, as a region of space gets denser, time slows down, and as the density approaches the density required to become black hole, time just freezes.
What you will see when looking at a "black hole" is just a region of space with the eventual event horizon of the hole just frozen in time, and as you move outside, time goes through the "molasses" stage, and as you get further away, gets normal.
Erm, no. See, the perception of time dilation is with respect to the frame of reference of the observer, not of the thing observed. You don't look from a region of low density space into a region of high density space and "see" that their time has slown down.
If you were outside the black hole observing, then you would see the black hole form instantaneously. Only from the perspective of the black hole's event horizon itself would time be stopped.
But it would still form -- the "stopping" is only in a relative sense to other frames of reference. The black hole would still form, the perception of the speed at which this occurs is all that varies, and it would be quite fast for anyone observing from "normal" space.
The enemies of Democracy are
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Real Daleks don't climb stairs - they level the building.
It is almost impossible to format formulæ on /. You state "false" with not further doc. Can you at least give links to docs supporting this?
don't cut it off www.mgmbill.org
https://www.eff.org/https-everywhere
In all seriousness, (oblig. IANAAP) The issue is that almost all models for a black hole (supermassive or otherwise) are based on mathematical equations. As in all equations, if you throw a data set at them, you get a result. Physicists then translate that number into a theoretical state of events.
Bottom line is, until someone jumps in one, and then comes back out to tell us about it, all we're doing is theorising.
Damn it! Now I have dead pixels in my screen!
Since gamma radiation is basically photons, shouldn't those be absorbed by the black hole as well?
So... are there MECOs or Black holes?
(oblig. IANAAP)
Sorry, but obscure acronyms in posts talking about strange far-off things leads the mind to wonder what it really does stand for in this case?
--Edward Dassmesser
Or to put forward another example: Icedancers. If they go into a spin, they pull their arms together and thus start spinning faster without actually using any other force to do so. Indeed, angular momentum made visible in a very obvious form.
Coz eternity my friend, is a long *ing time.
As far as I can tell, all those observations are compatible with the main alternative hypotheses to black holes as well, so it's wrong to say "black hole observed".