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Hidden Black Holes Discovered
mknewman wrote to mention a Space.com article discussing the discovery of a large group of hidden black holes. From the article:"Black holes cannot be seen directly, because they trap light and anything else that gets too close. But astronomers infer their presence by noting the behavior of material nearby: gas is superheated and accelerated to a significant fraction of light-speed just before it is consumed. The activity releases X-rays that escape the black hole's clutches and reveal its presence. "
Hidden Black Holes Finally Found
By Robert Roy Britt
Senior Science Writer
posted: 03 August 2005
01:24 pm ET
A host of hidden black holes have been revealed in a narrow region of the sky, confirming astronomers' suspicions that the universe is loaded with many undetected gravity wells.
Black holes cannot be seen directly, because they trap light and anything else that gets too close. But astronomers infer their presence by noting the behavior of material nearby: gas is superheated and accelerated to a significant fraction of light-speed just before it is consumed.
The activity releases X-rays that escape the black hole's clutches and reveal its presence.
The most active black holes eat so voraciously that they create a colossal cloud of gas and dust around them, through which astronomers cannot peer. That sometimes prevents observations of the region nearest the black hole, making it impossible to verify what's actually there.
These hyperactive black holes are called quasars. They can consume the mass of a thousand stars a year and are thought to be precursers to large, normal galaxies. The exist primarily at great distances, seen as they existed when the universe was young.
A few quasars have been identified, but many more are thought to await discovery, based on the total number of X-rays detected in broad sky surveys.
"From past studies using X-rays, we expected there were a lot of hidden quasars, but we couldn't find them," said study leader Alejo Martínez-Sansigre of the University of Oxford, England.
New observations with NASA's Spitzer Space Telescope cut through dust to spot quasars blocked by their own clouds, as well as other quasars hidden inside galactic dust.
Spitzer records infrared light, which penetrates dust. It found 21 quasars in a small patch of sky.
"If you extrapolate our 21 quasars out to the rest of the sky, you get a whole lot of quasars," said study team member Mark Lacy of the Spitzer Science Center at the California Institute of Technology. "This means that, as suspected, most super-massive black hole growth is hidden by dust."
The results are detailed in the Aug. 4 issue of the journal Nature.
Religion for nerds. Stuff that really matters
They found the Kessel system. http://www.atombender.de/swgwiki/index.php/Kessel_ System
Could things like this be part of the explanation for that "dark matter" that scientists are always talking about? Maybe there are more and we just haven't found them.
for hidden black holes.... what a job...
what was there when it all started: galaxy or a black hole?
OK, can one of you physics geeks explain to me why x-rays are able to escape the gravitational clutches of a black hole when light cannot? I've never understood this.
Reminder: Apple owns 1/255th of the internet.
someone want to explain how light gets trapped but not x-rays?
The holes that we don't know about should be called black holes since they are in the dark.
But the holes that we know about should be called white holes since we know about them.
Hmm.. that doesn't make sense does it?
What does your Credit Report look like?
Here's a Journal entry about previously unseen quasars (black holes, really) that was found by Spitzer, just by looking for infra red signatures instead of X-ray.
Quidquid latine dictum sit, altum sonatur.
Black holes bend space in every direction. Their effect on space is strongest closest to them, especially within their event horizon. But they bend all of spacetime, in every dimension, infinitely. At least to the distance in lightyears of the duration since their forming, and even before, when their spread-out mass still bent space, just not all in one place, and without the counter-intuitive effects within the event horizon.
So it seems that relying on detectors which detect only the behavior of light between the Earthly observer and the unobstructed black hole is pretty crude. How long before we have nanodetectors that detect the miniscule (nanoscule?) deflection of a laser within a small space on Earth, away from the "straight" path we'd expect from the influence of the space matter that we can see? Maybe we have to account for the "dark" matter also bending space in the Universe. But such a detector seems like a lot more reliable mapping instrument, for all these cosmic masses, than just waiting for some gas to drift across the view of our traditional scopes. How long until we can start to use really sophisticated Einsteinian relativity detectors?
--
make install -not war
i heard its near uranus
lameness filter thwarted.
Gee, doesn't that make you feel oh-so-safe for our upcoming space travel (many lifetimes ahead of us)... "a large group of hidden black holes." pot holes of the universe? You think driving is bad *now*...
Those X-rays don't "escape" the black hole because they aren't coming from inside the black hole. The idea is that as stuff falls into the black hole, it gets ripped apart at the atomic level. As it gets ripped apart, it emits x-rays. Because the matter hasn't quite reached the event horizon yet when this starts to happen, these x-rays are able to make it away from the black hole.
So in other words those x-rays aren't coming from the black hole. They're coming from just outside the black hole, the dying screams of the matter falling in. So no "escaping" is involved, not exactly.
Then there's Hawking radiation but that's different, I don't think those are X-Rays.
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
they must get mass estimates for these black holes, then multiply by the estimated number of them, and see if it makes up the missing mass. there is a good chance that dark matter has been answered.
i disable sigs
astronomers infer their presence by noting the behavior of material nearby: gas is superheated and accelerated to a significant fraction of light-speed just before it is consumed.
...whereas gas is superheated and accelerated to a significant fraction of light-speed just before it is expelled from your average CowboyNeal.
The only surefire protection against Microsoft infections is abstinence. - The Onion
It'll probably just turn out to be specks of grit on the scanner-scope.
the biggest black hole in the universe was the United States national debt.
Of course there are different shades of black. Anyone who has owned an all-black wardrobe can tell you that the colours still clash.
As the gas falls toward the black hole, it speeds up, creates friction, an releases the energy in the form of x-rays.
"`Ford, you're turning into a penguin. Stop it.'" -Douglas Adams, THHGTTG
It is worth noting that, as with any astronomical discovery outside our part of the Milky Way, the black holes may or may not exist now (or be in the same place) since we are seeing them as they were billions of years ago. They are "seen as they existed when the universe was young." [The Article] The speed of light causes the long delay between occurance and observation.
This sig has not been evaluated by the FDA. It is not designed to diagnose, treat, prevent, or cure any disease.
In the constellation of Cygnus
There lurks a mysterious, invisible force
The Black Hole
Of Cygnus X-1
Six Stars of the Northern Cross
In mourning for their sister's loss
In a final flash of glory
Nevermore to grace the night...
You are completely right. Slashdot is a total hoax. Now stop reading this site and commenting on it, and leave us alone. We'll be a lot better off without you.
Can anyone explain if the curent theories still speculate that eventually all the matter in the universe will be sucked up by black holes?
Also, once that happens will the black holes (as the only remaining objects in spacetime) start attracting each other? I'm hoping they don't reach some sort of a gravitational status-quo where our universe just becomes a universe of complacent singularities.
Nothing better to think about at 1:30 am on a Sunday morning than the death of the universe...
If you don't know what AltaVista is (was), get off my lawn.
The myth of Black holes and the pure gravitational view of a century ago will be the eventual demise of our society. Most of the astronomers and astrophysicists only see black holes cause their perception is filtered to see them. The 'effects' that make them think there is a black hole can be explained from other paradigms that are not based solely on gravity. I ask that during this century the standard community grows beyond this infancy and learns to embrace the view that plasma cosmology bestows upon us. Read books from Hannes Alfven, Anthony Peratt, Eric Lerner....
Beware, the article is quite technical:
If you extrapolate our 21 quasars out to the rest of the sky, you get a whole lot of quasars.
to the visible ones?
If you don't like the service, stop checking the articles and posting. All you achieve by doing either activity is increasing the ad revenue Slashdot receives. So you're rewarding slashdot for (what you apparently consider to be) a sub-par service.
They're always in the last place you look.
Maybe this is how gay clubs form, a black hole develops in the women's restroom and eventually it is just guys there. They think, "What the heck" and next thing you know your 'girlfriend' is this hairy dude named Kenneth who refers to you as 'bitch' and to add insult to injury, his penis is bigger than yours. That was the worst 8 years of my life....
Could things like this be part of the explanation for that "dark matter" that scientists are always talking about? Maybe there are more and we just haven't found them.
Well, yes, but only a small part. We can put a pretty good upper bound on the amount of dark matter that can be in black holes based on gravitational lensing data. Black holes most famously absorb light that is incident inside their event horizons, but they also cause light traveling outside to curve around it. (As does all matter.) Thus, a star that is behind a black hole looks to be in a different place than it should, or even at two different places at once (more info). We can measure how much light is bent and infer how much matter is contained in high-density regions.
Obviously, gravitational lensing only happens where matter is compact. Uniformly distributed stuff won't do it. Thus, we know about how much dark matter there is, and from this, roughly how much can be in black holes. The punch line is that only a small fraction of dark matter (I don't remember the statistic off hand) can come from black holes.
The question is obviously, then, where's the rest of this matter? Some could be in other "normal" matter, like dwarf stars, but again, for various reasons that can't account for very much. Some could be in neutrinos (weakly interacting particles which are almost impossible to detect). This still leaves a whole lot of matter unaccounted for though. Maybe it's so-called WIMPs (weakly interacting massive particles) which theoretically could be very massive but interact with normal matter very little. Read more at Wikipedia.
Good question, though.
So how do you tell X-rays generated by matter falling into a black hole from bremsstrahlung X-rays generated by energetic particles decelerated by super-massive (but not black hole) objects?
Inquiring minds want to know!
Hook line and sinker. If you don't like trolls you should stop feeding their ego by replying to them.
They're right.
You spend ages looking for one black hole, and then a whole bunch of them come along at once...
I missed the SUP tags being deleted... :(
Oh dear, are they missing again? I just set them down and they seemed to be sitting their without problem, probably just rolled under the potted hygrangia, I shouldn't wonder.
Not to worry though I have some spares in the closet, behind the rusted skates and the half box full of old green stamps books.
I'll just trot off and check shall I ?
that when I clicked on the link to the article, I was honestly expecting this
http://www.universetoday.com/am/publish/spitzer_f
http://www.nasa.gov/home/hqnews/2005/aug/HQ_05211
http://www.esa.int/esaCP/SEMPHV1P4HD_index_0.html
http://www.msnbc.msn.com/id/8812911/
More information of hidden black holes and their discovery.
"Sure there's porn and piracy on the Web but there's probably a downside too."
Example: It is possible, at room temperature and pressure, to have pure water at 105 degrees celcius and NOT have it boil. It is very unstable and will generally boil vigorously the moment you get any kind of circulation within the water.
Second, Quasars (Quasi-Stellar Objects) are, as yet, undefined. Nobody knows what drives them, so to call them super-active Black Holes is blatantly absurd. They are also frequently at the very edge of the visible Universe, making it very unlikely anything large enough to collapse into a super-massive Black Hole could have existed - let alone existed long enough to actually undergo gravitational collapse.
Besides which, such objects are not near. This is important. Black Holes evaporate, but they don't evaporate THAT quickly. A Black Hole the size of a typical Quasar would need to be absolutely gigantic and would not have evaporated in this time even if no other matter had fallen in.
Indeed, there are NO quasars closer than 5 billion light-years away - a distance referred to as the "red-shift cutoff". If Quasars were galaxy seeds, you would expect them to fade into the age of galaxies, not dramatically and suddenly cut off entirely.
The idea that Quasars then formed into galaxies is improbable - the diameter of a Black Hole is a direct function of the mass of the Black Hole (which includes the mass and effective mass of everything it consumes). It is unlikely that there are any galaxies large enough to have a Black Hole of the kind of mass implied by the output of a typical Quasar.
If a Quasar were powered by a Black Hole, it would be typically 100,000 times more massive than the Black Hole at the Black Hole at the center of our own galaxy. Given that the presence of a galaxy implies that the Black Hole is still being fed matter and energy, it would be quite impossible for a Black Hole to evaporate to 0.00001% of its original size in the time available.
Remember, Earth is 4 billion years old, the Universe is only 15 billion years old. And of those 15 billion years, the Black Holes would only start to really evaporate relatively late on as the density of matter and energy declined. Actually, you don't even get all 15 billion years of that. Quasars peaked at about 12 billion years ago and as already noted, vanished entirely at 5 billion years ago. This gives you a paltry 7 billion years to shrink to the required size.
Now we get into a real mess. The Milky Way galaxy is ALSO estimated at 12 billion years old, based on the ages of known structures. There are no structures around Quasars. They'd be blown to bits. For the Milky Way to have formed around a "dead" Quasar, the Quasar must have formed considerably earlier. There are a LOT of galaxies out there as old as, or older than, the Milky Way. If all of them formed around Quasars, there would have needed to have been more of these really early starters than existed at the height of the reign of Quasars.
There is another problem. The Milky Way belongs to a local cluster of galaxies. If they ALL had formed around dead Quasars, the Quasars would have fallen into each other from their gravitational pull LONG before there was any possibility of a galaxy forming.
Nor are Black Holes strictly "hidden". They always emit Hawking Radiation, although there are no good detectors for this at present. That is hardly the fault of the Black Holes, though - if they're not seen, it's because the observers aren't looking.
As for the number of Quasars - there are only 39 known Type II Quasars
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
What about /dev/null?
"Sure there's porn and piracy on the Web but there's probably a downside too."
When asked why it took this long to discover the nature of the strange space phenomenon, Mark Lacy of the Spitzer Science Center at the California Institute of Technology replied:
"Well, the thing about a Black Hole, its main distinguishing feature, is it's black. And the thing about space, your basic space color, is black. So how are you supposed to see them?"
"Derp de derp."
There is nothing more guaranteed to expose the embarrassing ignorance of the basic slashdotter re physics than black holes.
You're a douch bag. I'm going to hunt you/you're family down, kill them, burn your house down, and salt the earth so nothing will ever grow there again. Frosty pissy bastard.
Is this actually one of the few moments in Slashdot news when "Nothing to see here, please move along" is literally true?
This slashdot-related signature is a stub. You can help kihjin by expanding it.
are god's answer to /dev/null
Howcome X-Rays can ESCAPE the gravitational pull of black holes? Are they FTL or is it something else?
"It's always the way, isn't it? We've been in space for three million years and there hasn't been one. Then all of a sudden, five of them turn up at once."
BlackHole == Windows == Holes being found all the time... what am I missing?
"I'm going to f***ing bury that guy, I have done it before, and I will do it again. I'm going to f***ing kill Google"
Just think, if you can find a straight line near our solar system that passes through two black holes, with a bit of work you might be able to create the biggest telescope ever... assuming the lens geometry works. Okay, okay, there's loads of impracticalities and the issue of lens geometry, but it's a nice idea.
First
"Black holes cannot be seen directly, because they trap light and anything else that gets too close."
Then
But astronomers infer their presence by noting...(that) X-rays...escape the black hole's clutches and reveal its presence. " MAKE UP YOUR MIND
Rimmer: But a Black Hole's a huge, compacted star! It's millions of miles wide! Why didn't you see it on the radar screen?
Holly: Well, the thing about a Black Hole, its main distinguishing feature, is it's black. And the thing about space, your basic space colour is black. So how are you supposed to see them?
Rimmer: But five of them! How can you be ambushed by five Black Holes?
Holly: Always the way, isn't it? You hang around in deep space for three million years and you don't see one. Then, all of a sudden, five all turn up at once.
Well, hidden compared to the obvious ones in the quarterpanel of your Corvair.
Are there any obvious black holes in outer space? There must be. Rush wrote a song about one.
This is pretty impressive too:/ isee3_traj.gif
http://heasarc.gsfc.nasa.gov/Images/misc_missions
Mmm... Pretty colours... Mmm...
--
If you want to be accurate, the circumference is a direct function of the mass; the diamater may well be infinite.
Good, inexpensive web hosting
x = -|x| - 1
Re[x] = -|x| - 1
Im[x] = 0
x is pure Real
For x > 0
x = -x - 1
2*x = -1
x = -1/2 (fails premise)
For x 0
x = x - 1
x = -Inf
Sqrt[x] = +/- i * Inf
Never thought of that... physics rules!
where obviously our laws of physics don't operate
I don't see it is so obvious that the laws of physics are not usable to discuss the inside of a black hole. Newton's 3 laws (inertia, F = ma, and equal and opposite reaction), for instance - can you explain why they have no validity in a black hole? Well, to start with, there ought to be mass in the black hole due to the gravitational effects we feel on the outside, right?
The laws of physics are the null hypothesis (statistics). Although we cannot accept the null hypothesis in our world, we don't reject it. I am not a black hole scientist, so I need to ask what evidence do we have to reject the laws of physics for the inside of a black hole?
Know your pads. One time pad: good for cryptography. Two timing pad: where to take your mistress.
"Hidden black holes discovered". That's just not possible, if something is hidden then by definition it hasn't been discovered yet. Unless, some hitherto unknown alien intelligence discovered them first and hid them.
Otherwise, it's just your basic newly discovered black hole.
'That large sucking sound you hear is your economy being devoured by the black holes of unwinable wars...'
Or as Carl would have said it:
"Billions and Billions and Billions of dollars, all lost forever in the sands of time..."
What the fuck is a douch bag? Douche bag!
Cfx
You have 2 nucular Moderator Points! Use 'em or loose 'em!
Hidden African-American Holes Finally Found
By Robert Roy Britt
Senior Science Writer
posted: 03 August 2005
01:24 pm ET
A host of hidden African-American holes have been revealed in a narrow region of the sky, confirming astronomers' suspicions that the universe is loaded with many undetected gravity wells of color.
African-American holes cannot be seen directly, because they trap light and anything else that gets too close. But astronomers infer their presence by noting the behavior of Affirmative Action nearby: gas is superheated and accelerated to a significant fraction of light-speed just before it is consumed.
The activity releases White Women that escape the African-American hole's clutches and reveal its presence.
The most active African-American holes eat so voraciously that they create a colossal cloud of gas and dust around them, through which astronomers cannot peer, and believe me, they don't want to. That sometimes prevents observations of the region nearest the African-American hole, making it impossible to verify what's actually there.
These hyperactive African-American holes are called quasars, but never to their faces. They can consume the mass of a thousand stars a year and are thought to be precursers to large, normal galaxies. The exist primarily in the Projects, seen as they existed when the neighborhood was young.
A few quasars have been identified, but many more are still at large, based on the total number of X-rays detected in broad sky surveys.
"From past studies using X-rays, we expected there were a lot of hidden quasars, but we couldn't find them," said study leader Alejo Martínez-Sansigre of the University of Oxford, England.
New observations with New York Attorney General Elliot Spitzer Space Telescope cut through dust to spot quasars blocked by their own clouds, as well as other quasars hidden inside galactic angel dust and crack.
Spitzer records infrared light, which penetrates dust. He found and arrested 21 quasars in a small patch of Central Park.
"If you extrapolate our 21 quasars out to the rest of New York City, you get a whole lot of quasars," said study team member Mark Lacy of the Spitzer Science Center at the California Institute of Technology. "This means that, as suspected, most super-massive African-American hole growth is hidden by angel dust."
The results are detailed in the Aug. 4 issue of the journal American Gangsta Hip-Hop Weekly.
Blow me, douch e bag. Don't you have a cousin to go impregnate, grammer Nazi? Heil.