Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
Science

More Blackholes Discovered... 161

Posted by CmdrTaco from the including-one-in-your-head dept.
Lispy writes "Space.com has this story about the surprising finding of missing blackholes. There might be up to five times more blackholes in space than previously estimated. "The European Southern Observatory in Munich, Germany reports that the black holes were all in "active" galaxies, meaning they were actively consuming large quantities of galactic matter.""
This discussion has been archived. No new comments can be posted.

More Blackholes Discovered... More

More Blackholes Discovered...

Comments Filter:

  • there they are!! (Score:5, Funny)

    by SKPhoton ( 683703 ) on Sunday May 30, 2004 @09:57AM (#9289289) Homepage
    Black holes play hide and seek? I never saw that one coming.
    • Man, we're in a world of shit if someone shouts out "Olly-Olly outs in free!"
    • "It's always the way innit? 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!"

      Or perhaps:

      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 color... is black. So how are you supposed to see them?

  • Kinesis 1.1-3 (Score:4, Funny)

    by nomannerofmanatall ( 784027 ) on Sunday May 30, 2004 @10:04AM (#9289310)
    "At the beginning there was
    nothing but a big ball of
    gases.
    For a long time it just sat there
    in the nothingness, getting hotter
    and hotter.
    Then it exploded."

    • Re:Kinesis 1.1-3 (Score:4, Funny)

      by Roland Piquepaille ( 780675 ) on Sunday May 30, 2004 @10:08AM (#9289334)
      "At the beginning there was
      nothing but a big ball of
      gases.
      For a long time it just sat there
      in the nothingness, getting hotter
      and hotter.
      Then it exploded."

      Are you saying the Creator of the Universe ate refried Mexican beans?
    • At the beginning there was a point
      of almost infinite
      matter.
      Then it exploded.
      Thus began time and space.
      • At the beginning there was a point
        of almost infinite
        matter.
        Then it exploded.
        Thus began time and space.

        "Or something like that."

        "And you can make up history
        from the present as easily
        as I can.
        For is this not the principal
        gift of the education you
        paid so many dollars to obtain?"

        • "And so I say to thee:

          The universe was
          created in order
          to amuse us."

          Or whatever :)
          • "We don't know if there are
            Gods,
            Or even one God,
            Who made everything all by
            himself,
            Completely from scratch,
            But we don't believe that everything
            is just some big accident
            either,
            Because that's what a lot of
            you think
            And look at you."

    • Civilization 1-2-1 (Score:2, Interesting)

      by Epistax ( 544591 )
      In the beginning,
      the Earth was without form,
      and void.

      But the Sun shone upon the sleeping Earth
      and deep inside the brittle crust
      massive forces waited to be unleashed.

      The seas parted
      and great continents were formed.
      The continents shifted, mountains arose.
      Earthquakes spawned massive tidal waves.
      Volcanoes erupted
      and spewed forth fiery lava
      and charged the atmosphere
      with strange gases.

      Into this swirling maelstrom
      of Fire and Air and Water
      the first stirrings of Life appeared:
      tiny organisms,
      • "Until the clever apes were
        all alone on the earth, with the
        exception of the other living
        things and many, many trees
        that could be turned into pointed
        sticks."
    • In the beginning there was nothing. Then God said "Let there be light.", and there was still nothing, but you could see it.
      • "In the beginning was the void,
        and the void was all there
        was, for a long time.
        And then there was something
        that was not the void,
        Although maybe it still was,
        Really,
        And just looked like it wasn't,
        Being an illusion,
        And a pretty convincing one
        at that,
        To everything that was part of
        the illusion,
        Unless it wasn't an illusion,
        But really separate from the void,
        And actually came into existence
        somehow,
        Even though it's impossible
        to know,
        And wouldn't change anything
        anyhow,
        Because this was a long
        long
    • In the beginning,
      There was darkness,
      Then there was light,
      Then some more darkness,
      Then it was light again,
      Then the humans arrived,

      And it rained.

  • What if (Score:4, Interesting)

    by Progman3K ( 515744 ) on Sunday May 30, 2004 @10:05AM (#9289312)
    What if there are black holes being formed constantly, appearing in pen space even WITHOUT there having been a star there?

    The universe could be collapsing, with black holes appearing faster and faster, exponentially more and more of them.

    Well, I for one welcome our new black hole overlords.

    • Re:What if (Score:3, Funny)

      by minator ( 744625 )
      Why? They suck!

    • Re:What if (Score:5, Informative)

      by Mister Transistor ( 259842 ) on Sunday May 30, 2004 @10:24AM (#9289382) Journal
      As far as we know, black holes result from the collapse of a star. They don't just "appear" for no reason. The new ones discovered were obscured by their accretion disks and the torus of gas and matter surrounding them.

      That's like saying what if dead bodies suddenly started appearing everywhere - without there having been live people first. Corpses don't just "appear" out of nowhere, they have to be made :)

      • Re:What if (Score:4, Insightful)

        by cozziewozzie ( 344246 ) on Sunday May 30, 2004 @10:49AM (#9289467)
        Actually, it's not such a ridiculous statement. I remember reading in a popular science book (can't remember if it was "Brief History of Time" or "In Search of the Big Bang") that some scientists are speculating about the existence of ultra-small black holes to 'solve' the problem of missing matter. Such "mini black holes" would not be a product of stars collapsing.

        Unfortunately, I cannot remember more, just that Hawking himself considered it a possibility. He pondered about using them in place of power plants :-)

        • Re:What if (Score:4, Interesting)

          by Xenographic ( 557057 ) on Sunday May 30, 2004 @11:31AM (#9289641) Journal
          Oh, with some high energy experiments, they expect that they might create really tiny black holes.

          Of course, they also expect that these will very quickly dissolve due to Hawking radiation. In other words, they won't ever last long enough to suck anything much up...
          • Even if the lab-made singularities did have plenty of time to exist, they wouldn't "suck" anything because their mass isn't large enough to cause that kind of gravity.

            High gravity causes black holes. Not the other way around.

            I'm hesitant to even use the term "black-hole" regarding lab-made singularities because I'm not sure if they even have an event-horizon.
            • Hawking style singularities theoretically have an event horizon. It's typically much smaller than the size of a proton or neutron, so it's pretty difficult for normal matter to cross it, and the amount of time for something to 'get lucky' and tunnel in is many orders of magentude more than the amount of time for the same mass of virtual particles to tunnel out. However, this is a function of environment. A 'quantum' black hole the mass of say, a baseball, floating in empty space would last for a tiny fracti
        • Yeah, I remember. Those mini-black holes were supposed to be remnants from the creation of the universe, that have disapated so much that right now they're `mini-'.

          ie: no collapsing sun, etc., but they still needed a major event to be created.

          Actually, I think Hawkings once said that taking all the hydrogen from the Earth oceans to make a hydrogen bomb, might make a mini- black hole.
      • As far as we know, black holes result from the collapse of a star. They don't just "appear" for no reason. The new ones discovered were obscured by their accretion disks and the torus of gas and matter surrounding them

        But the problem is that we don't know really much about them. The black holes were discovered first theoretically by studying the consequences of Einstein equations by Karl Schwarzschild [colorado.edu] around 1915. So "we" (as in "we, humans") knew about the black holes years before the very first empiric
        • That's why I qualified it with AFAWK ;)

          Anything is possible, but I prefer to err on the side of causality - things don't just appear - they either moved there or evolved there from somewhere or something else.

          But as I said, anything is possible including the fact that maybe black holes shift dimensionally or something and could "pop up" at random where nothing existed previously, but it existed _somewhere_ before that, I would think.

          But that then begs the question, and this is taking it to the extreme, w

      • Re:What if (Score:5, Insightful)

        by shaitand ( 626655 ) * on Sunday May 30, 2004 @12:57PM (#9290050) Journal
        Yes but we don't have any evidence or basis for believing their collapsed stars in the first place AFAIK. That's just a guess.

        AFAIK we've never actually seen a star collapse and a black hole appear... that wouldn't even be proof but it certainly would be the least of what we'd need to see before claiming that IS how they are formed. Rather, it's just our best guess of what could create this thing we call black hole.

        Again AFAIK, the closest thing to evidence we have of this are computer simulations which... assuming we haven't botched a variables and all other relevant GUESSES are correct shows that the collapse of a star COULD cause the formation of a black hole.

        That means it's theoretically possible... not that it's an exclusive contract or even that it's likely enough to actually happen in reality. Lot's of things are theoretically possible.

        For example, it's theoretically possible (and probably can be proven via a controled computer simulation designed for that purpose) a gust of wind could blow through a crack in your window. The gust could shift the air currents in such a way that it pins a paper on your desk against your monitor and rolls it up reasonably tightly. Then the wind shifts and pops the roll off your desk onto your chair standing upright on end. And then in the morning when still sleepy you sit down for your morning coffee without noticing and ream yourself.

        So you see damn near anything is theoretically possible. And if it's theoretically possible it can be proven via computer simulation, we control the initial variables. We set the computer to try different initial gusts until one works. But more importantly, our world works the way it really works, but in the simulation physics work the way WE THINK they work. Potentially a very big difference there.
        • Actually, it's the collapse of a LARGE amount of matter and/or energy that causes them, we think. The supermassive ones that appeared just after the big bang weren't collapsed stars (yet), just huge blobs of matter that didn't quite form a galaxy correctly. So I sit corrected - But I agree anything is possible - see my reply to the post above yours...

          • Oh come on now, admit you got a chuckle out of my example of what's theoretically possible ;)

            This is one my pet peeves, I don't think we do nearly enough questioning of what we generally think of as fact in physics.

            Black holes are good example, they teach that they are collapsed stars as fact in grade and high school. They teach alot of these theories (that aren't even truely theories, merely hypothesis) as fact.
        • AFAIK we've never actually seen a star collapse and a black hole appear... that wouldn't even be proof but it certainly would be the least of what we'd need to see before claiming that IS how they are formed. Rather, it's just our best guess of what could create this thing we call black hole.

          Its pretty much the only way. Most of what is 'out there' is gas. When areas of this gas collapses it gets dense and hot. When it gets dense enough and hot enough it starts to undergo nuclear fusion, forming a star

  • Wrong. (Score:5, Informative)

    by Anonymous Coward on Sunday May 30, 2004 @10:06AM (#9289320)
    Although some say that these black holes account for the "missing matter" that is needed for the universe to gravitationally collapse upon itself some hundreds of billions of years in the future, current analysis shows that the mass of all black holes are less than one trillionth of the mass of the universe.

    Even if there are a thousand more times the number of black holes out there, it still won't account for the so-called "missing mass".

    Of course, there could be many million times more black holes out there. Or some other large masses that we have yet to find. In any case, this 2-to-5 times the number of black holes isn't the (possible) mass we're looking for.

    • Re:Wrong. (Score:1, Interesting)

      by Anonymous Coward
      misc_pondering

      By some process, matter turns into dark matter. By measuring the amount of dark matter, we can determine the age of the universe. /misc_pondering
    • Why do physicists continue to assume that the theory must be correct when the evidence seems to point at its being wrong? There is not as much mass in the universe as predicted by theory. Physicists say the universe is wrong, but wouldn't it make more sense to say that the theory is wrong? Isn't that the basis of the scientific method. "Missing Matter" isn't science, it's pseudo-science.
      • No self-respecting physicist will ever say "the Universe is wrong". That statement is just pure nonsense. The universe is what it is, nothing more and nothing less.

        Now, you can ask why do physicist still think the "theory" is correct. Well, the truth is that physicist never think the "theory is correct", it is only approximately correct.

        Also, no theory predicy the amount of mass in the universe. The amount of matter measured by its gravitational effects (given to us by general relativity theory) is more t

  • Does this change anything? (Score:5, Interesting)

    by stealth.c ( 724419 ) on Sunday May 30, 2004 @10:08AM (#9289330)
    Does this make the theory of a "big crunch" any more likely than before? I'm guessing not.

    The theory which I understood to be most prominent at present was one of an accelerating, expanding galaxy. Eventually, all galaxies would be moving away from one another so swiftly it would be impossible to see one galaxy from another. Every galaxy would sputter and die in a universe its inhabitants would perceive as utterly empty.

    Does the discovery that black holes are more prominent than before just mean that the pace of destruction of said galaxies will only be any different? Or does it do anything to reverse the present theory? It's possible there's no change at all. Any galaxies like this that were seen (in the article) were behaving that way billions of years ago. Who knows what's going on now.

    Also, I wonder what could trigger the Milky Way's black hole into an "active" state. Heck, it may already have happened, but it would take about 50,000 years for us to see it.

    • Re:Does this change anything? (Score:1, Interesting)

      by Anonymous Coward
      IANACD (not a Cosmologist dude) but galaxies won't move away from each other, instead space between them moves away. These black holes don't really mean much for the end of the universe, there will be no Big Crunch (well as far as we know it today). 70% of the universe is still "Dark Energy" that expands space.

      • Assuming the Big Bang theory is correct, the galaxies are moving away from each other, since the universe is expanding.

        Also, dark energy (and "bright" energy, for that matter) doesn't expand space. Energy is interchangeable with mass, which exerts and feels gravity. More mass increases the possibility of a Big Crunch; without dark energy, it is believed that the universe would expand forever for lack of sufficient gravity to counteract the initial bang.

    • Also, I wonder what could trigger the Milky Way's black hole into an "active" state. Heck, it may already have happened, but it would take about 50,000 years for us to see it.
      I'm not sure what you mean. Black holes are block holes - there's no such thing as an "active" or "passive" black hole, just a black hole. If one does exist at the center of our galaxy, it will be sucking things in.

      • Re:Does this change anything? (Score:4, Informative)

        by barakn ( 641218 ) on Sunday May 30, 2004 @02:51PM (#9290775)
        The idea of a black hole 'sucking' things in is wrong. If our own sun was to turn into a black hole, the planets wouldn't suddenly get ripped out of their orbits and inexorably dragged (kicking and screaming) into it. Black holes, like all other massive accreting objects, have to wait for stuff to come their way. At the center of a galaxy, where matter is denser (more stars, more gas), things around the black hole can get involved in a massive traffic jam. The losers are sent by collisions or gravitational interactions on orbits straight towards the hole. Eventually the hole eats so much of the traffic that there's no longer a traffic jam. The objects orbiting around it don't interact with each other enough to get sent towards the hole, and the hole is now on a strict diet. This is the state of our own Milky Way. If our galaxy were to collide with another, a density wave of stars and gas might get sent towards the black hole, and it would start to eat again. So, yes, there are active and passive black holes.
      • I'm not sure what you mean. Black holes are block holes - there's no such thing as an "active" or "passive" black hole, just a black hole. If one does exist at the center of our galaxy, it will be sucking things in.

        He was referring to this quote from the article:

        The black holes were all in "active" galaxies, meaning they were actively consuming large quantities of galactic matter. Our Milky Way contains a supermassive black hole but the setup is not currently active. In an active galaxy, a swirling disk

      • Supporting the previous responses...

        Whether or not the black holes are active or passive has nothing to do with the black hole and everything to do with the black hole's environment.

        A black hole is passive if it simply exists and all the nearby stars are quietly rotating around it (because it is very massive) instead of being "sucked" in.

        A black hole is active if they is a bunch of gas (stars, etc.) that is too close to the black hole. Note that a very large star in the same environment would suck in
    • It makes me wonder about the dark matter / dark energy theories that are floating around. It would seem to have pretty large implications to them.

      As I understand it, scientists somehow figured out how much matter there "should be" in the universe. This has always sounded somewhat dubious to me, but whatever. Not surprisingly, the amount there should be is not equal to the amount there actually is. So they invented this dark stuff, which they say also fuels the expansion of the universe.

      Now, if we found

  • Remove "surprising" from story. (Score:5, Insightful)

    by Chatmag ( 646500 ) <editor@chatmag.com> on Sunday May 30, 2004 @10:14AM (#9289345) Homepage Journal
    How can someone be surprised by this find? What we know about the universe is virtually nothing in comparison to what is out there.
  • I've always wanted a blackhole as a pet ... but where would I hide it from my parents? ... let alone feed it? :P
  • The Zen Buddhist in me would love it if the expansionary universe became a cyclical big bang/crunch.
  • I was just looking for my black hole this morning. Thanks for the heads up - i called the researchers and they're sending it back to me Fed Ex.
  • I don't want to be a conspiracy theorist, but there is other explanation for all the gravitational effects, missing matter, galaxies not expanding etc... There is a possibility of "antimatter" with antigravity property. This can explain why galaxies are not expanding as the theory would predict. Some says it's the mass of the neutrinos, some says it's the gravitational equation that bounds to a minimum, and some other explain that we simply live with a parallel universe (no SF here), wich can only intera

    • Re:Just don't consider this as a fact (Score:1, Informative)

      by Anonymous Coward
      Um, antimatter doen't gravitationally repel. Maybe that's why you put the word in quotes? Anyway, the acceleration of the universe is already explained by the gravitational repulsion of dark energy.

      Incidentally, theory does not predict that galaxies should be expanding. It predicts that distant galaxies should stay the same size (being gravitationally bound), but should expand away from each other, which they are.
    • Occam's Razor [vub.ac.be]

      "Occam's razor is a logical principle attributed to the mediaeval philosopher William of Occam (or Ockham). The principle states that one should not make more assumptions than the minimum needed. This principle is often called the principle of parsimony. It underlies all scientific modelling and theory building. It admonishes us to choose from a set of otherwise equivalent models of a given phenomenon the simplest one. In any given model, Occam's razor helps us to "shave off" those concepts,

      • Re:Just don't consider this as a fact (Score:5, Insightful)

        by cozziewozzie ( 344246 ) on Sunday May 30, 2004 @10:57AM (#9289500)
        With all due respect to sir Occam, the solution which appears to be the simplest is not always the simplest, simply because there is so much we don't know. Especially about black holes, missing matter, unified field theory and such fundamental questions.

        I mean, a proton was such a lovely, simple thing, before they went ahead and turned it into a gazzilion complicated nonsensical sub-particles :-)
        • If by a gazillion, you mean three (quarks), then no. :-) Quarks do make the hordes of different particles easier to understand, it just happens that protons and neutrons seem to be the most common ones.
          • Quarks themselves are held together by gluons. Quarks have mass, so they interact by exchanging gravitons. And of course the quarks are charged, so they exchange virtual photons. Suddenly your three quarks have turned into a menagerie of particles all packed into a single proton.

      • Re:Just don't consider this as a fact (Score:4, Insightful)

        by johannesg ( 664142 ) on Sunday May 30, 2004 @11:28AM (#9289629)
        I cannot read french, so I cannot comment on the article, but I can tell you that Occam's razor only applies to theories that explain all phenomena. If a theory is extremely simple, but fails to explain certain phenomena, then despite the razor, it is wrong.

        Since the more usually accepted theory fails to account for certain phenomena (where is all that mass?), it is conceivable that a more complex theory is required instead.

        Anyway, I'll go back to pretending I'm a software engineer now ;-)

      • Just because there are more black holes does not mean there is more mass than previously thought.

        It just means there are more black holes.

        Remmeber, black holes are all about density, not mass. For any given density, there is a size at which a black hole would be seen to an outsider.

        • >Remmeber, black holes are all about density, not mass. For any given density, there is a size at which a black hole would be seen to an outsider

          I seem to remember from my physics class that in fact the only thing that mattered after the creation off a black hole was its mass, electric charge and rotation. All other properties like density, and shape got lost or meaningless afterwards.

          Of course in the time *before* the singularity is created the density would be very important, since it would be needed
          • It's all relative to your point of view.

            To an outside observer. a black hole has density.

            It has a defined volume as we see it, and a defined mass.. therefore one can calculate density.

            The comcept of a singularity is not all a black hole is about. When we say "black hole" we are not talking about just a singularity, but the entire phenonenon we observe... defined to us by the event horizon. We aren't speaking as to what is "inside" becuase, by definition, we cannot. Our observations are limited by the ev

      • Re:Just don't consider this as a fact (Score:5, Insightful)

        by Trurl's Machine ( 651488 ) on Sunday May 30, 2004 @12:47PM (#9289974) Journal
        Occam's Razor (...) Don't make things more difficult then they have to be. Black holes are the simplest explanation

        With all due respect to the advantages that Occam's Razor has given to the advance of science, this was exactly the key factor that made the leading scientist of late XVIII century like Antoine Lavoisier [wolfram.com] to judge that stones cannot fall from the sky. [adam.com.au] In 1768, 1794 and 1795 there were substantial sightings of meteorite showers in France, Italy and England - yet according to the Occam's Razor, it was easier to explain them by assuming the witnesses just lie. Use Occam's Razor as any razor - with extreme caution.
        • Mod parent up to a 5. I hear this principle stated far too often, and Occam's Razor is used to blindside many possibly correct but more complex theories.
        • As another example of the problems with Occam's razor and cosmology...

          Several physical modes, including notably Guth's inflationary hypothesis (which is pretty much the standard model these days) assume certain physical ratios and constants start out randomized, and many astrophysicists have interpreted this to imply there might be an infinite number of "parellel" universes, which can never be observed. (Witness the last chapter of Carl Sagan's Cosmos, as well as Hawking, Timothy Ferris, and others).
          No

    • Re:Just don't consider this as a fact (Score:5, Interesting)

      by Jerf ( 17166 ) on Sunday May 30, 2004 @03:32PM (#9291033) Journal
      There is a possibility of "antimatter" with antigravity property.

      FYI, in English (since you reference a French site), "antimatter" is charge-reversed matter. It still has positive mass and therefore, standard positive gravity.

      You're looking for word(/phrase) "negative mass".

      Note that negative mass emits a negative gravity field and therefore repulses everything, though; based on your haphazard explanation it's not clear if you're trying to claim negative mass would emit a gravitational field that attracts other negative mass.

      That's just a nomenclature point. Here's a criticism: Every theory I've ever seen like that focuses in on how their exotic theory could explain something, but then completely fails to draw out the rest of the conclusions of that exotic matter. For instance, see the discussion on Exotic Matter [wikipedia.org] in Wikipedia. Negative mass may explain some things, but it would also produce a boatload of other effects which we haven't seen.

      Dark energy, in my mind, remains a better theory.

      • Whoops, whack third paragraph (Score:4, Informative)

        by Jerf ( 17166 ) on Sunday May 30, 2004 @03:35PM (#9291053) Journal
        Whoops, whack my third paragraph. Wikipedia says it all better and probably more accurately.
      • Under the theory of General Relativity, you're absolutely right.

        Under a few other (relatively obscure and incomplete) models of gravity that are possibly true (that is, they accord with relativity in all so-far observed effects), antimatter can have variant gravitational effects, although the mass-energy content is the same as ordinary matter. This could range anywhere from a few percent difference to antigravity.

        Since there has been no successful experimental measure of the effect of gravity on antimatt
  • black holes were all in "active" galaxies, meaning they were actively consuming large quantities of galactic matter.

    Black Holes are the first intergalactic corporation.
  • As if black holes aren't confusing enough...

    These black holes were not "missing" because nobody thought they existed. This /. article calls the report "surprising", but their existence would not be surprising if they were known to exist but had not been located.

    • These black holes were not "missing" because nobody thought they existed. This /. article calls the report "surprising", but their existence would not be surprising if they were known to exist but had not been located.

      The thing surprising thing about it is if it revealed an opposite-of-the-consensus-guess, which might have been why it was so. If I were to look in the dishwasher and find a sock, it would be surprising because I had not anticipated or known that a sock would be in the dishwasher, althoug

  • either its... (Score:5, Funny)

    by 3seas ( 184403 ) on Sunday May 30, 2004 @11:19AM (#9289595) Homepage Journal
    father physics and mother natures way of recycling or ....

    there is only so much space so every now and then things need to be archived compressed....or..

    astronomy is like the computer industry... where the user/observer can never get there from here... there is always something missing....or...

    we still don't know what gravity really is.... or... maybe MS has the answer... make people need you... again and again and again.....

    And on that note.... I have a few black holes up for sale.... they contain everything you need and want... and as soon as we figure out gravity then we can unpack them...
    • I have a few black holes up for sale.... they contain everything you need and want... and as soon as we figure out gravity then we can unpack them...

      That's completely unnecessary. Black holes are self-extracting. :)

  • God does not play dice (Score:2, Funny)

    by Anonymous Coward
    but he does do Enron style accounting. Where does all that matter go?

  • ...they're black. And the thing about the monitor screen, is that it's black.

    time passes

    Well, the thing about grit is, it's black...

  • I'm not surprised (Score:4, Funny)

    by rixstep ( 611236 ) on Sunday May 30, 2004 @12:31PM (#9289892) Homepage
    Black holes are known to multiply - especially in spring, which is probably why we're seeing them now.
  • How can scientists know that there are blackholes if they cannot see them?

    • Re:How can scientists know...? (Score:4, Informative)

      by alienmole ( 15522 ) on Sunday May 30, 2004 @01:45PM (#9290331)
      How can you tell there's a mosquito in the room when you cannot see it?

      RTFA:

      Black holes cannot actually be seen, because they trap all matter and light that enters them. But if an active galaxy is viewed from above, the hole in the middle of the torus allows a good view of the accretion disk, allowing astronomers to infer the presence of the black hole.

      The new study looked at galaxies that were edge-on, but deduced the black holes by studying emissions in various wavelengths of the electromagnetic spectrum.

    • Re:How can scientists know...? (Score:1, Informative)

      by Anonymous Coward
      What the other guy said. I believe they also emit various sorts of radiation.

      Some other neat stuff: near black holes, there are pairs of little particles popping into existence, smashing into each other, and annihilating each other. If this happens at just the right point at the event horizon, the particles fail to annihilate each other -- one falls in, and the other goes shooting out into the universe.
    • If you look at the behaviour of some stars you can see that they are orbiting something massive. If its really massive and you can't see it, its probably a black hole. If an object is massive enough, and its not keeping itself spread out because of heat (like a star that has run out of fuel) it will inevitably collapse into a black hole. You can measure the size of some objects by how rapidly they flicker. If things change in a matter of hours, then the effect can be no larger that that number of light-

  • Big Duh from this AGN astronomer (Score:3, Informative)

    by mbrother ( 739193 ) <mbrother.uwyo@edu> on Sunday May 30, 2004 @05:46PM (#9291764) Homepage
    This is yet another example of a non-story story. 99.9% of all astronomers would have told you before this story that these active galaxies had big black holes. We would have also pointed to other results (from Hubble) from the last 5 years or so that have clearly indicated that essentially ALL massive galaxies -- active or not -- harbor black holes in their cores about 1/1000 as massive as the bulge component of the host galaxy. I've been saying this to my classes and in seminars for years. I'm not saying this isn't a nice project, seeing the waste heat from the active core, but it's a confirmation not a "discovery of new black holes." Sheesh.

  • Los Lonely Boys (Score:3, Interesting)

    by Graymalkin ( 13732 ) * on Sunday May 30, 2004 @05:53PM (#9291787)
    The real cool thing with this story is the fact the black holes were discovered using the Astronomical Virtual Observatory (AVO). The AVO is a giant database of images take from a variety of telescopes including Hubble, Chndra, and the VLT in Chile.

    Hubble for instance aquires about a terabyte of data every year. Some projects under development now will collect that much data every single day. Virtual observatories let anyone grab some of this data to work with it. There's a lot of new information being collected or digitzed every day which means just that much more data to mine for every region of the sky.

    An excellent example of this (besides this recent discovery) is the research done on the KBO 2001 KX76. A team of European astronomers used a program called Astrovirtel based out of the European Southern Observatory to better map the orbit of the KBO. They were able to parse over data going back to 1982 which means they were able to watch almost 20 years worth of the KBO's orbit. One of the researchers was even able to perform some of the processing work on his home computer. The orbital mapping of 2001 KX76 gives credence to the theory that it is actually larger than Ceres and thus the largest space rock discovered in the solar system thus far.

    Virtual astronomy can easily find information on just about any observed object that varies by some bit over time. Examining old plates has been a hallmark of astronomy for years but these new virtual observatory projects take the concept to a higher level. The discoveries of these black holes is a testament to how useful it is to be able to mine through years of observations from entirely different types of observatories. For some types of research it makes telescope time, which is typically hard to come by, a bit less important. It also opens the door for anyone to do astronomical research.

    Virtual astronomy is really open source astronomy. The collective work of hundreds of individuals can be leveraged by just about anyone. These same people can also contribute back to the VOs for other people down the road to work with.

Slashdot Top Deals

As long as we're going to reinvent the wheel again, we might as well try making it round this time. - Mike Dennison

Close