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Black Hole Observed by X-Ray Satellite

Zonk posted more than 7 years ago | from the it's-waaay-out-there dept.

143

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."

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Obligatory summary (4, Funny)

GroeFaZ (850443) | more than 7 years ago | (#16379877)

"Nothing for you to see here. Move along."

Re:Obligatory summary - Exactly (3, Funny)

russ1337 (938915) | more than 7 years ago | (#16380129)

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.

Re:Obligatory summary - Exactly (1)

mattcoz (856085) | more than 7 years ago | (#16381837)

Of course you can't see a black hole, but you can observe the effects of it.

Looking at a black hole (-1, Redundant)

BrokenBeta (1007449) | more than 7 years ago | (#16379885)

I tried to open the thread and got "Nothing to see here, move along". I guess that is appropriate.

Screenshot (5, Funny)

GillBates0 (664202) | more than 7 years ago | (#16379887)









Re:Screenshot (0, Funny)

Anonymous Coward | more than 7 years ago | (#16380203)

Hey bozo, your post didn't contain anything. And for some reason you got modded up as funny.

Re:Screenshot (1)

xenoarch (817676) | more than 7 years ago | (#16380303)

thats the joke..

Re:Screenshot (1)

bodan (619290) | more than 7 years ago | (#16383501)

Whooooosh!

Re:Screenshot (1)

4D6963 (933028) | more than 7 years ago | (#16380467)

Hey bozo, your post didn't contain anything. And for some reason you got modded up as funny.

Your post did contain something. And for some reason you didn't get modded up. I wonder why ;-)

If you still ain't got the joke, his post said "Screenshot", and all you see was nothing, because there's nothing to see when you look at a black hole.

Re:Screenshot (1)

HotBBQ (714130) | more than 7 years ago | (#16380533)

You sir/maddam, should run for Congress.

Your sig (OT) (1)

DeadCatX2 (950953) | more than 7 years ago | (#16381909)

"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.

Re:Screenshot (1)

steveo777 (183629) | more than 7 years ago | (#16380325)

Ahh... the elusive 'white spot'. Quite the opposite of the black hole. It has no gravity whatsoever.

Re: No, really... (2, Funny)

Namlak (850746) | more than 7 years ago | (#16380615)

  • <---Here's the actual image

Be careful (0)

Anonymous Coward | more than 7 years ago | (#16379889)

Sometimes when you look into the event horizon, the event horizon looks back.

Seeing into a black hole? (1)

ackthpt (218170) | more than 7 years ago | (#16379925)

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...

Re:Seeing into a black hole? (2, Insightful)

Anonymous Coward | more than 7 years ago | (#16380053)

What good would worrying about a black hole do? It's not like we can push it away...

Re:Seeing into a black hole? (3, Funny)

XxtraLarGe (551297) | more than 7 years ago | (#16380207)

Well, maybe YOU can't push it away...

Re:Seeing into a black hole? (1, Funny)

Anonymous Coward | more than 7 years ago | (#16381417)

Chuck Norris can!

Re:Seeing into a black hole? (2, Informative)

MyLongNickName (822545) | more than 7 years ago | (#16380385)

Actually, you could. Get a massive object on the opposite side of the black hole. Get it close enough that you can maintain a thrust that will keep you at a steady point relative to the black hole. Make sure thrust is angled so it will not "strike" the black hole.

Using this process, gravity will pull the black hole away.

Now, this would take one hell of a lot of energy to do, but it is possible.

Re:Seeing into a black hole? (1)

4D6963 (933028) | more than 7 years ago | (#16380525)

lol, yeah, using a huge star. I'm not sure what your plan consists in anyways, but I think the best would be to "throw" the biggest star you can from where you stand to the side of the black hole, to have the black hole to capture the star (in its orbit, not inside of its event horizon) and become a binary system. If you throw your star fast enough you'll get the new binary system to move away from you.

Re:Seeing into a black hole? (2, Insightful)

MyLongNickName (822545) | more than 7 years ago | (#16380603)

If this is your plan, then it would not matter whether it orbited or not. You could just throw it in the event horizon. Wouldn't matter.

Re:Seeing into a black hole? (2, Insightful)

4D6963 (933028) | more than 7 years ago | (#16380997)

You could just throw it in the event horizon

Are you sure? I thought about that and it just didn't appear obvious to me, although it would make sense, I just thought making them a binary system was a safer bet.

Re:Seeing into a black hole? (2, Insightful)

MyLongNickName (822545) | more than 7 years ago | (#16381871)

The momentum of the system is the same regardless of the configuration of the system..

Re:Seeing into a black hole? (1)

bodan (619290) | more than 7 years ago | (#16383545)

Yes, but maybe he wants to reuse the star :)

So the question is... (1)

jftitan (736933) | more than 7 years ago | (#16380805)

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!

Re:Seeing into a black hole? (1)

PagosaSam (884523) | more than 7 years ago | (#16381867)

They are studying super massive black holes are the center of galaxies. You are going to need to throw a lot of stars at that sucker, like millions!

Re:Seeing into a black hole? (1)

Firehed (942385) | more than 7 years ago | (#16382647)

I thought the whole premise of a black hole was that nothing came out of it. Surely whatever we're observing has some pretty special properties if it can escape a black hole when even light can't do such a thing.

Re:Seeing into a black hole? (1)

Anthony (4077) | more than 7 years ago | (#16383177)

IANAAP (AP=Astro-Physicist) but my understanding is what we can observe is the "dying screams" of matter as it is dragged into the blackhole (hence the high-energy radiation - X-Rays). At the precise boundary, matter and energy are transmitted in either direction, into or away from the black hole in directions as shown in the models.

Re:Seeing into a black hole? (1)

x2A (858210) | more than 7 years ago | (#16383285)

Nope [colorado.edu] .

(note that this isn't what they're observing, but x-rays from just outside the blackhole, but I thought i'd point it out for interests sake)

it's a start (2, Insightful)

mikesd81 (518581) | more than 7 years ago | (#16380043)

it almost gives me hope that the world might one day be united in space exploration."

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.

Re:it's a start (0, Flamebait)

wanerious (712877) | more than 7 years ago | (#16380383)

Well, as long as you're allied with the present US administration. The newest space policy statement just released would "deny this freedom to our adversaries", speaking of the freedom of space exploration.

Re:it's a start (1)

Iron Condor (964856) | more than 7 years ago | (#16383929)

Why was this modded flamebait? It is absolute objective truth. Something like Cassini, a European mission with American instrumentation, guidance, control and coms will never happen again because of the pigheadedness of the current US administration. This is NOT "flamebait". This is NOT "a troll". This is simply the exact precise consequences of the actions of the Bush Whitehouse and the Republican Congress.

Anybody who imagines improving international scientific exchange is either deluded or lying. ITAR and EAR have forced many nations around the globe to develop their own rocket engines, their own deep-space communications systems, their own attitude-control systems because the US will not allow foreigners access to these any more. The US has expressly and intentionally given up a great head-start and advantage on space-technology. If you disagree with that, then don't downmod the messenger, but kick YOUR senator and YOUR president out of office.

Re:it's a start (0)

Anonymous Coward | more than 7 years ago | (#16380511)

Err, what is it you think scientists do now?

Re:it's a start (0)

Anonymous Coward | more than 7 years ago | (#16381315)

I'm less optimistic. Human history is entirely about competition with the story sometimes devolving into murder. The story does not have to be told as 'man vs man' but can be 'man vs environment/nature'.

The only way I see all of humanity uniting is against a common lethal foe. But even then, man has already directed such agents to harm other men - biological warfare is an excellent example of this.

Working together produces some great achievements but the purpose always originates from some underlying conflicts, even while each participant may have a different purpose/comflict.

Normally I'm quite an optimist, but not on such topics. Eventually, we turn on each other. If you're not the aggressor, then some other guy will be and then you have to become aggressive to defend yourself.

Sorry to be a downer.

Serious Question (1)

MyLongNickName (822545) | more than 7 years ago | (#16380093)

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?

Re:Serious Question (2, Interesting)

Anonymous Coward | more than 7 years ago | (#16380179)

Strictly speaking, we have no knowledge about what happens inside the event horizon - we can't, by definition. However, we know the forces are extremely strong at the event horizon, and they'd only get stronger as it collapses still further, and we know of no force that would stop the collapse, so the logical conclusion is that it collapses to infinite density.

Re:Serious Question (5, Interesting)

Anonymous Coward | more than 7 years ago | (#16380505)

PhysicsPhil has a pretty good explanation. Here's another way of phrasing it.

Electrons, neutrons, and so on don't really exist as volumes, but rather as forces. Think about a balloon filled with air; it takes up space, but the only reason it does is because of the pressure of the air inside pushes out on the surface.

Now, if you squeeze the balloon, it'll shrink. The more you squeeze, the smaller it gets. If you could squeeze as hard as you please, you can continue to shrink the balloon smaller and smaller.

Particles are like that. Gravity is unique in that it's a force that can get infinitely strong, so it can overcome any other force, and squeeze everything together down to an arbitrarily small point.

Interestingly, from the perspective of a star collapsing into a black hole, it never actually quite makes it, as time slows down as gravity becomes stronger. It's like Zeno's paradox: If you try to go from point A to point B, crossing half the distance each time, do you ever get there? Intuitively, you'd think no, but if you take an infinite number of steps, yes.

In other words, black holes, from the perspective of the black hole, take forever to collapse down to a singularity. However, from our perspective outside the black hole, the singularity forms essentially instanteously, as our subjective time speeds up relative to the black hole's subjective time.

(As a side note, we don't have a theory of quantum gravity, so we don't actually know what the absolute center of a black hole is like, but we do understand the physics up to and past the event horizon, all the way to the singularity, all of which is just subject to general relativity. All the effects with astronomical significance occur outside the event horizon, as information that goes past there is effectively meaningless.)

Re:Serious Question (1, Interesting)

Anonymous Coward | more than 7 years ago | (#16381033)

Actually, there is NO force inside of an event horizon. There can't be, because time does not exist inside an event horizon, and force is a function of time.

Re:Serious Question (2, Informative)

PhysicsPhil (880677) | more than 7 years ago | (#16380369)

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.

In some sense, you have to trust that physicists know what they're doing. Absent an understanding of the math, it really is an act of faith that black holes are not one big practical joke.

That being said, you may remember the Exclusion Princple from high school chemistry, which basically says particles like electrons and neutrons can't occupy the same (quantum) states. When you try and push them together, they push back. It is possible to calculate the maximum force (pressure actually) that such a system can produce. After that, there's nothing can keep a star from collapsing.

If you're interested in reading, check out "Electron degeneracy pressure" in an undergrad quantum mechanics textbook or on the Wikipedia.

Re:Serious Question (1)

RingDev (879105) | more than 7 years ago | (#16380613)

So if time is a measurement of the movement of energy, and space is the (quantum) state of sub atomic particles, and no two particles can share the same state at the same time, then would it be a plausible explaination to say that the particles have moved in time in some way we are unable to measure?

-Rick

Re:Serious Question (5, Informative)

khayman80 (824400) | more than 7 years ago | (#16380431)

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.

Good question. Short answer: we don't know.

Long answer: According to the General Theory of Relativity, black holes have all their mass contained in a geometric point called the "singularity". This singularity is surrounded by a finite-sized spherical boundary called the "event horizon" which is defined as the locus of points where not even light can escape the gravity of the singularity. Because nothing (that we know of) can travel fast than light, the event horizon is a seemingly impenetrable barrier to any investigation of the singularity itself.

So we're unlikely to view a singularity directly and measure its size. On the other hand, most physicists are convinced that the General Relativistic description of the singularity as a literal geometric point most be wrong. They believe this because very small objects are governed by quantum mechanics, and a new theory (which does not exist yet) called "Quantum Gravity" must take over at densities like those found in singularities.

I'm generally a fairly skeptical chap, and it took a long time to even convince me that event horizons exist. For the longest time, all "proofs" of black holes basically said "here is something that is more dense than a neutron star, and since the ONLY THING more dense than a neutron star is a black hole, this object must be a black hole." I was never really convinced that there weren't other objects denser than neutron stars that didn't actually have event horizons, so this argument never swayed me. These recent observations seem to conclusively prove that event horizons exist, but singularities are an entirely different matter. We'll have to wait for the final word on that subject...

Re:Serious Question (0)

Anonymous Coward | more than 7 years ago | (#16380697)

so is the black hole pulling things in from all directions as a spherical point? or does it have a shape?

Re:Serious Question (2, Informative)

meringuoid (568297) | more than 7 years ago | (#16381499)

so is the black hole pulling things in from all directions as a spherical point? or does it have a shape?

It's conventional to treat the event horizon as the surface of the black hole - in which case, yes, it has a shape. The mathematically simplest black hole is the Chandrasekhar black hole, which is nonrotating and spherical. Realistically, however, a black hole will be formed by the collapse of a star, and conservation of angular momentum implies that it will be spinning very rapidly, at least to begin with. This is the Kerr black hole [wikipedia.org] , and it has some very peculiar effects on the region of spacetime around it. There's a zone called the ergosphere, from which it is possible to escape, but in which it is completely impossible to stand still...

Re:Serious Question (1)

mentrial (956547) | more than 7 years ago | (#16381621)

Well, the event horizon is spherical, that we know. Which could suggest that the actual matter inside is ordered in an spherical kind of way (if it has any volume at all).
But the thing is that we don't know, just a while ago we where certain that the only thing that we could ever really know about a black hole are the characteristics of its event horizon (mass, angular momentum and electric charge).

Its just called "event horizon" because the only fastest way that information of an event can travel is the speed of light (in the form of ... light! ;P). So if even light cannot scape, then we can never ever know anything of the insides of the event horizon, some quantum theorists would say that since we (or anyone or anything, even if you where alive in the inside) can ever know the inside, it doest exist, so a black hole is ONLY its mass, angular momentum and electric charge.

However just very little time ago Hawkings said that we *could* theoretically know what is inside because of the quantum's effect on the edges of the event horizon (the quantum's particles inside the event horizon could change the particles outside). So THEORETICALLY there is a way of knowing what is inside of a black hole because, thanks to those little quantum devils, a real event horizon never forms.

Anyway, no one knows if we (or anyone or anything) could ever hope to develop some technology capable of "seeing" inside of a black hole (the quantum effect would be in the very edges, so to collect information of the inside of a black hole, you would still need to travel at the speed of light (or so close to it that it wouldn't matter).
  I would say that its almost certain that in some really far (as a couple of ups in the kardashev scale far) future we could have the energy requirements for proving or disproving the string "theory" before having the energy requirements for retrieving information from a black hole.

Re:Serious Question (1)

0xABADC0DA (867955) | more than 7 years ago | (#16381319)

There is an easy proof that black holes exist:

0

As in zero, the number. QED. They are a physical manifestation of this concept, and like mass/0 they have 'undefined' density. Incidentally, this is also the reason why we have String Theory (although that does not actually exist). ;-P

--
I don't think QED means that I think it means...

Re:Serious Question (2, Interesting)

meringuoid (568297) | more than 7 years ago | (#16380457)

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.

'No space between the smallest particles' is basically what a neutron star is. It's essentially a mass of neutrons edge to edge, held up by the quantum-mechanical requirement - the exclusion principle - that no two particles can occupy the same quantum state.

However, there's a limit to this state. In general relativity, mass isn't the only thing that produces gravity: pressure does too. Pile on extra mass to a neutron star and its gravity increases - and so does the internal pressure. The upshot is that the pressure approaches infinity at about five solar masses; the neutron star can only collapse (the actual limit may be much lower, last I heard it wasn't precisely known).

Thus if general relativity is correct there's nothing that can prevent the total collapse of a five-solar-mass neutron star. Propose a force that can resist it, and it can only do it by upping the pressure still further, and hence the gravity it must oppose... The star collapses to zero volume and infinite density, the notorious singularity hidden inside the event horizon.

All that said, though, it's probable that the star does not reach zero volume. General relativity is known to be unreliable on the very small scale of quantum mechanics, and quantum mechanics is known to be unreliable where very large masses are concerned, so the applicable physics when you compact five solar masses to a volume smaller than an atom is anybody's guess...

Common Misconceptions about a Black Hole (2, Interesting)

plluke (412415) | more than 7 years ago | (#16380477)

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.

Re:Serious Question (1)

necro81 (917438) | more than 7 years ago | (#16380485)

It depends, in part, on which theory you are using to describe the conditions inside the event horizon. General Relativity will say that, without question, the black hole's mass will collapse on itself down to a single, infinitessimal point which, because it has finite mass and zero volume, has infinite density. It is, as some people say, what happens when God divides by zero. Others call it a singularity, which has all kinds of mathematical connotations.

Quantum Mechanics, on the other hand, doesn't like to cut it so fine. Things like infinite density or existing at an infinitessimal point are anathema in QM. A QM description of the singularity would use a probability density function, which would effectively smear the (very large, but finite) mass over a (very small, but nonzero) region of space. Just as the probability density is smeared out, so too would the mass density, indicating a non-infinite density.

Who's right? Probably neither. This is a case that demonstrates the seeming irreconcilability of relativity and quantum mechanics. It's the kind of thing that people far smarter than me that been grappling with for decades.

Re:Serious Question (1)

osu-neko (2604) | more than 7 years ago | (#16380709)

Of course, any disagreement about what's beyond the event horizon is a philosophical disagreement, not a scientific one. :)

Re:Serious Question (1)

greylion3 (555507) | more than 7 years ago | (#16381575)

Einstein didn't like the notion of black holes either.
I favor the theory that they are in fact MECOs, not black holes.

http://en.wikipedia.org/wiki/Magnetospheric_eterna lly_collapsing_object [wikipedia.org]

Favorite quote: "[Quasar] Q0957+561 has a magnetic field, which a black hole cannot have."

If we find that 'black holes' have magnetic fields, then they are MECOs instead - at least until a better theory comes along.

Re:Serious Question (1)

wrook (134116) | more than 7 years ago | (#16382067)

Hmm... I'm not a physicist, but perhaps I can reword things in a way that will help you view things in a different way. Someone has already replied with a similar reply, but I'm not sure it is obvious what they are saying.

If you look at "particles" in an atom as being real physical objects (like raisons in an oatmeal cookie), it's hard to understand that they can be compressed. But you can't directly observe* a "particle" as small as an electron (or even smaller), because they don't behave like matter on a macro scale.

The position of an electron, for instance, isn't determined by directly observing it, but by observing the effect that it has on other particles. As two particles get closer together, they exert a force, repelling each other. The closer they get, the more force they exert. So generally, you can't make two particles overlap. The two partcles don't "hit" each other, they just don't generally exist closer than a certain distance. The distance defines their "position".

As we look closer and closer, we discover that these "particles" aren't really particles in the normal sense at all. They don't have an absolute "position" or boundaries. They actually only have a probability that the particles are in a certain position (high probability to be near the "center" of the gross "position" and lower probability further out. The "particle" actually teleports between these "positions" (and as far as I know, spends 0 time at any one "place"). So it's more like a fuzzy cloud.

So if you can imagine that a particle isn't actually something "physical" the way we normally define "physical", but rather something that repels other things and has an indeterminant position, you might be able to understand a bit more clearly how they can compress to a single point. If the "particle" itself takes up no actual space and it is only the effect on other "particles" that defines it's size, then it's no problem for many particles to occupy the same space.

But you can imagine that the effect of doing that would be very strange indeed. Gravity is trumping the repulsion forces of the particles. So what kind of properties does such an object have? We're just starting to figure that stuff out...

Note, the way I've explained it could be totally wrong (and in fact, our current model could also be totally wrong). I write this only to suggest a different way to look at the situation. Once you've wrapped your brain around the idea that things work differently on the micro scale than the macro scale, you can pursue a better explanation from someone (who didn't drop out of physics...)

* Of course, we can't "directly observe" anything (with the possible exception of our own thoughts). If we "see" something, we are observing the light that bounces off that object. If we "touch" something, we are merely "feeling" the repulsion forces of other particles. And of course each one of these things has to be interpretted by our minds. It is important to understand that in physics, it is not really possible to directly observe objects whether they be micro or macro.

If this black hole actually emits xrays (2, Insightful)

LiquidCoooled (634315) | more than 7 years ago | (#16380109)

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?

Re:If this black hole actually emits xrays (3, Informative)

Anonymous Coward | more than 7 years ago | (#16380273)

The X-rays aren't coming "out of" the black hole; they're emitted by the incoming matter getting crunched to oblivion just outside of the event horizon.

Re:If this black hole actually emits xrays (1)

ajs (35943) | more than 7 years ago | (#16380489)

The X-rays aren't coming "out of" the black hole; they're emitted by the incoming matter getting crunched to oblivion just outside of the event horizon.


Yes and no. Certainly that makes up the vast majority of the light shed from the region around an event horizon, but there are other sources of radiation. Hawking Radiation, for example.

Re:If this black hole actually emits xrays (4, Informative)

iamlucky13 (795185) | more than 7 years ago | (#16380963)

Because Hawking radiation scales inversely to the area of the event horizon, the Hawking radiation from anything but extremely small black holes (which we don't even know actually exist) is negligible and far below what we have the ability to detect. It is literally less than the background radiation of space.

For practical purposes, the grandparent is correct, if a little simplified.

You may find it interesting though, that if small black holes actually do exist (they would have to be incidental products of the Big Bang), we may be able to detect their last moments of evaporation by Hawking radiation as x-ray/gamma ray bursts. Some researchers are plan to look use data from one of NASA's upcoming x-ray observatories to look for such flashes that can not be attributed to other known sources.

Re:If this black hole actually emits xrays (1)

ajs (35943) | more than 7 years ago | (#16381895)

Because Hawking radiation scales inversely to the area of the event horizon, the Hawking radiation from anything but extremely small black holes (which we don't even know actually exist) is negligible and far below what we have the ability to detect.


Yes, but as I pointed out, that's just one of the better known forms of radiation eminating from the region of a black hole. Other forms include the extragalactic jet formed by the interaction between the black hole's magnetic field lines and its accretion disk and lensing of radiation from other sources.

Re:If this black hole actually emits xrays (1)

aexiphixion (529171) | more than 7 years ago | (#16381993)

no because then everyone would get confused between a brown dwarf and uranus

Re:If this black hole actually emits xrays (0)

Anonymous Coward | more than 7 years ago | (#16383749)

Disclaimer: My information might be out of date or inaccurate, however this is all as I understand it. Please correct me if you know better, as I'd like to know if I'm wrong in my understanding.

Other answers have stated some of the reasons X-rays appear (they're not from the blackhole itself) and Hawking radiation (from the blackhole, but not really measurable in most cases). The interesting property of Hawking radiation that I recall reading about is that it doesn't contain any information about the materials that went in to the black hole to form it.

For instance, you can burn a piece of paper with ink on it. Practically it is, for all intents and purposes, destroyed. However, with proper technology, you *could* reassemble the resulting ashes and plasma and recreate the original piece of paper since all the original information was preserved.

Black holes apparently disobey this law of conservation of information at the quantum level. So while a star burning nuclear fuel emits particles that contain information about the materials they were formed from, a black hole does *not*. This would create a very big distinction between a black hole and other super dense cosmic entities.

Great, now that's something else to be scared of.. (2, Funny)

Channard (693317) | more than 7 years ago | (#16380133)

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!

Re:Great, now that's something else to be scared o (1, Funny)

Anonymous Coward | more than 7 years ago | (#16380403)

Giant kittens are comforting?

Re:Great, now that's something else to be scared o (1)

IflyRC (956454) | more than 7 years ago | (#16381533)

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.

Re:Great, now that's something else to be scared o (2, Insightful)

nizo (81281) | more than 7 years ago | (#16380667)

Wrong branch of science. You might try a major pharmaceutical company or your local drug dealer instead.

Getting closer.... (2, Interesting)

jfengel (409917) | more than 7 years ago | (#16380137)

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".

Re:Getting closer.... (0)

Anonymous Coward | more than 7 years ago | (#16380259)

I thought it meant that they were observing phenomenom closer to the edge of the black hole itself than they previously had.

Re:Getting closer.... (1)

Hoi Polloi (522990) | more than 7 years ago | (#16380353)

"Closer to the edge" refers to resolving power, not space vs ground. Since they are observing in the x-ray frequencies they have to observe from space. Ground based x-ray astronomy is impossible due to atmospheric absoarption.

Re:Getting closer.... (1)

Tired and Emotional (750842) | more than 7 years ago | (#16380565)

They probably mean closer to the singularity. That would translate into harder (higher frequency, more energetic) x-rays. So the statement would amount to saying they are observing harder xrays than has been possible in the past.

Mod Parent Up (0)

Anonymous Coward | more than 7 years ago | (#16381253)

This is exactly what the article was talking about. The wording choice on the submission title is a little confusing, but they are talking about emissions from matter closer to the center of the accretion disk, not from a black hole closer to earth or at a higher resolution.

working together to blow everybody's heads off. (-1, Flamebait)

justkarl (775856) | more than 7 years ago | (#16380189)

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."

Space agencies, maybe. But citing US politics and a recent Slashdot article [slashdot.org] , I believe that space exploration is mostly driven by military gain. An unfortunate truth that Bush thinks the whole point of space is to keep big guns to point at people. And space agencies are funded by who????

Re:working together to blow everybody's heads off. (1)

osu-neko (2604) | more than 7 years ago | (#16380611)

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.

God is a Dentist. (0)

Anonymous Coward | more than 7 years ago | (#16380215)

In other news, Scientists have trained a large X-Ray telescope at a distant Dentist's office and made their own copy of the patient's teeth.

Why would nature go through the effort of hyper accelerating or heating material when she can just as easily create X-Rays the same way the local dentist does, with electricity?

The result of hyper heating gasses is a plasma which is very conductive and a very electrical phenomena. The easiest way to make plasma is to run a current through something.

Whee!

Whiney Liberal Comment (-1, Troll)

Anonymous Coward | more than 7 years ago | (#16380435)

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."

More bullshit whiney rhetoric from the left.

Apollo-Soyuz http://en.wikipedia.org/wiki/Apollo-Soyuz [wikipedia.org]
Shuttle-Mir http://spaceflight.nasa.gov/history/shuttle-mir/ [nasa.gov]
NASA/ESA Hubble Space Telescope http://eu.spaceref.com/ [spaceref.com]
NASA/Brazilian Space Agency http://asia.spaceref.com/news/viewpr.html?pid=1257 [spaceref.com]

Re:Whiney Liberal Comment (2, Interesting)

meringuoid (568297) | more than 7 years ago | (#16380673)

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."

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?

The paper (3, Insightful)

drxray (839725) | more than 7 years ago | (#16380451)

The MCG -6-30-15 paper [arxiv.org] 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.

The Japaneese have finally done it... (2, Funny)

BlabberMouth (672282) | more than 7 years ago | (#16380513)

they invented the Sudoku satellite. But what does that have to do with black holes?

Relative distances (1)

CopaceticOpus (965603) | more than 7 years ago | (#16380561)

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?

Re:Relative distances (1)

Kingrames (858416) | more than 7 years ago | (#16380803)

That's only true 50% of the time.

You may hand over your geek badge at the nearest station.

Re:Relative distances (1)

untree (851145) | more than 7 years ago | (#16382775)

That's quite an oversimplification. If you take into account both the moon's orbit and the distribution of the Earth's population, I think you would find it's far less than 50% of the time. There are angles between "up" for Shaq and "up" for whichever individual you select, and a third angle with wherever the Moon is in its orbit.

Just sayin'.

Wow... space time ripple (1)

McNihil (612243) | more than 7 years ago | (#16380587)

Aug 2005! And here I thought it was 2006 for almost a year now... weee I am one year younger... oh... maybe not.

There are no black holes (0, Troll)

viking80 (697716) | more than 7 years ago | (#16380967)

First, the diameter of a "black hole" is proportional to its mass. The sun, for example, must be compressed to a diameter of about 3km to become a black hole. A black hole with the mass of billion suns would have a dameter=3 billion km or the size our solar system. The density of this black hole would be "low" as in much thinner than air. (Do the math yourself. Mass of sun is 2x10E30kg)

By size, we mean the event horizon.

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.

The black hole will not form in any finite time since time there just stopped!

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, and the observer will first hand know the ultimate fate of the universe in a distant future.

Also, if you happend to be in a region of space that was getting close to become of a big black hole, you would not notice much.

If you comment on this, please give me the actual physics and math, It is not very complicated. Yes, I know many scientists disagree with me.

Just think for yourself for a minute.

Re:There are no black holes (0)

Anonymous Coward | more than 7 years ago | (#16381811)

I agree that black holes cannot seem to form. That means that black holes are asymptotic limits, and there's no point in speculating what would happen at or inside the event horizon since there's no way to experimentally verify the theory.

There are black holes (and stop karma whoring) (1, Informative)

Anonymous Coward | more than 7 years ago | (#16381965)

Your arguments were wrong the first time you posted them [slashdot.org] , 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 [nasa.gov] .

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 [nasa.gov] .

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"?

Re:There are black holes (and stop karma whoring) (1)

viking80 (697716) | more than 7 years ago | (#16382653)

I am sharing with you dear slashdotters an insigth that only few have, and that will change mankind forever. Any you, ungratful ones, are responding with quotes, and suggesting karma whoring.

Take a few seconds. Then take a deep breath, and try something new:

Think for yourself. Think outside the box.

Re:There are black holes (and stop karma whoring) (0)

Anonymous Coward | more than 7 years ago | (#16382995)

You asked for physical and mathematical arguments. I gave you them. You respond with simple-minded platitudes. Are you going to post an actual rebuttal, or merely continue to insist that anyone who gives reasoned scientific arguments why black holes do exist must be an unthinking conformist? I am perfectly capable of verifying for myself that the equations of general relativity do predict the existence of black holes. Are you?

Re:There are no black holes (1)

hxnwix (652290) | more than 7 years ago | (#16382205)

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.

Just in...:) (1)

bigbang19 (958410) | more than 7 years ago | (#16381203)

Scientists just discovered that the telescope had a hole in it and they were actually looking at a different hole.

Question about black holes (0)

Anonymous Coward | more than 7 years ago | (#16381231)

Why do the mass that enters black holes, or are in some way attracted to it (like for spiral galaxies) typically form a disc shape?

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.

Re:Question about black holes (2, Interesting)

meringuoid (568297) | more than 7 years ago | (#16382007)

Why do the mass that enters black holes, or are in some way attracted to it (like for spiral galaxies) typically form a disc shape? 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.

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...

Re:Question about black holes (1)

QuantumPion (805098) | more than 7 years ago | (#16382215)

Why do the mass that enters black holes, or are in some way attracted to it (like for spiral galaxies) typically form a disc shape?

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.

International cooperation leads to stagnation (1)

Dammital (220641) | more than 7 years ago | (#16381393)

"... it almost gives me hope that the world might one day be united in space exploration."
I hope that doesn't happen. International cooperation gave us the ISS: a project without a mission. Competition got us into orbit and to the Moon. Competition is good.

Re:International cooperation leads to stagnation (2, Insightful)

R3d M3rcury (871886) | more than 7 years ago | (#16382801)

Competition got us into orbit and to the Moon.
And, once the competition was over, there was no need to go back. That's the problem with competition: Once you've won the race, it's over. You go home and rest on your laurels.

Personally, I like the idea of cooperation towards a goal. It seems to improve the chances that we'll stay awhile. Heck, ISS has been manned for something like five years.

The obligatory question: (1)

Conanymous Award (597667) | more than 7 years ago | (#16381779)

But is it supermassive?

Re:The obligatory question: (1)

Alizarin Erythrosin (457981) | more than 7 years ago | (#16383047)

Well, some of the observations were of a galaxy's central black hole. In that light, I might have to say "yes".

Clocking the speed of a black hole's spin rate? (0)

Anonymous Coward | more than 7 years ago | (#16381941)

Is it like measuring the length of a building's height?

Hope! What hope? (4, Informative)

IEEEmember (610961) | more than 7 years ago | (#16382035)

it almost gives me hope that the world might one day be united in space exploration

I guess you missed yesterday's story [slashdot.org] 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."'

Which galaxy (1)

zenithcoolest (981748) | more than 7 years ago | (#16382085)

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

Time to update the Wiki (1)

DanTheLewis (742271) | more than 7 years ago | (#16382133)

http://en.wikipedia.org/wiki/Black_hole [wikipedia.org]

Someone better hurry. This is a fast-developing situation, and no one knows what'll happen to the article when the MECO [wikipedia.org] people get their hands on it.

Those aren't black holes. (1)

Tarlus (1000874) | more than 7 years ago | (#16382997)

They're yellow holes.

Nah, (0)

Anonymous Coward | more than 7 years ago | (#16383867)

they're Fry Holes.

What if two black holes collide? (1)

fahrbot-bot (874524) | more than 7 years ago | (#16383923)

Serious question. Any speculation as to what would happen should two black holes get caught in each other's event horizons?
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