Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×
Space Science

Astronomers Planning To Image Milky Way's Central Black Hole 68

99luftballon writes "Astronomers are planning the Event Horizon Telescope project in Arizona on Wednesday — and say in three or four years they should be able to image the ring of matter around the supermassive black hole at the center of the Milky Way. The black hole is 26,000 light years away, but should be large enough to check if Einstein got his equations right."
This discussion has been archived. No new comments can be posted.

Astronomers Planning To Image Milky Way's Central Black Hole

Comments Filter:
  • Event Horizon huh?
    Scientists have a sick sick humor!
  • by Samantha Wright ( 1324923 ) on Wednesday January 18, 2012 @07:09PM (#38743224) Homepage Journal
    Will people ever stop checking your equations?
    • by arnodf ( 1310501 )

      Let's hope not. Thanks to this we're discovering new great things again and again!

    • by jd ( 1658 )

      I maded you a relativistic equation, but I eated it.

      • by dissy ( 172727 )

        I maded you a relativistic equation, but I eated it.

        Does that look anything like this [wordpress.com]?

        • by jd ( 1658 )

          Definitely. Grabbity-stealing... *shakes head and heads off to the brake rume for cake, then realized he's on the wrong site for that*

    • by Anonymous Coward

      No because no one should ever stop checking any equations. All scientific formulae are an estimation to explain observations of reality. The relativity formula should never have been accepted as law. It should not be used to deny anything that doesn't fit the formula. It should have just been accepted as a "best guess" because better methods of observation and testing will one day replace that formula with something even more accurate. And after that there will be yet more accurate formulas, as long as scie

    • They'll stop when they find a problem. That's how science works.

    • Re:Oh, Einstein. (Score:4, Insightful)

      by interkin3tic ( 1469267 ) on Wednesday January 18, 2012 @08:09PM (#38743866)
      Untested hypotheses that turn out to be wrong often set research back months or years, wasting time testing them. Taking one man's word as law without testing it, if it were wrong, that could cause a huge amount of wasted time.

      It would suck if we didn't get teleporters within our lifetimes just because Einstein was a little off and no one bothered to check it.
      • by Nyder ( 754090 )

        ... Taking one man's word as law without testing it, if it were wrong, that could cause a huge amount of wasted time..

        Tell that to the dictators in the world...

    • by Anonymous Coward

      Well, if it's any consolation, you got a chuckle out of me, Samantha.

      Some of the other posters, however, need to lighten up a bit...

    • Will people ever stop checking your equations?

      Apparently not; from Einstein himself explaining why this is so: "If my theory of relativity is proven successful, Germany will claim me as a German, the Swiss will say I'm a Swiss Citizen and France will declare that I am a citizen of the world. Should my theory prove untrue, France will exclaim that I am Swiss, the Swiss will say I'm a German and Germany will declare that I am a Jew."

  • Oh Noes! (Score:2, Funny)

    by fazil ( 62946 )

    Divide by ZERO!

  • by bazald ( 886779 ) <bazald@[ ]ipex.com ['zen' in gap]> on Wednesday January 18, 2012 @07:32PM (#38743488) Homepage

    Liberate tutemae ex inferis!!!

  • by Black Parrot ( 19622 ) on Wednesday January 18, 2012 @07:37PM (#38743560)

    but should be large enough to check if Einstein got his equations right.

    The ongoing thingy with CERN's maybe-FTL neutrinos may answer that before the three or four years envisioned for this.

    • The ongoing thingy with CERN's maybe-FTL neutrinos may answer that before the three or four years envisioned for this.

      Apparently three or four years from now they'll figure out how to use FTL to make neutrinos travel backwards in time, so they sent us some so we'd know how important it was to continue the research.... now it all makes sense!

  • by Anonymous Coward

    It's black. Duh.

    • by Anonymous Coward

      Black holes don't really have a color. They just suck like that.

  • by Anonymous Coward

    Sadly, We'll have to pay $10 to see this copyrighted picture,,,

  • Oh, /. (Score:3, Funny)

    by Anonymous Coward on Wednesday January 18, 2012 @08:09PM (#38743864)

    All these posts in a story about a "black hole" and not one goatse link?

    • Re: (Score:2, Funny)

      by Anonymous Coward

      Be patient grasshopper.

  • by MetricT ( 128876 ) on Wednesday January 18, 2012 @08:44PM (#38744150)

    They're not imaging the event horizon, they're trying to image the accretion disk around the central black hole, and hoping they can see the event horizon's "shadow" against it. I doubt that we're going to be directly imaging the event horizon for the central black hole anytime soon.

    The Milky Way's central black hole is 4.l million solar masses. The Schwartzchild radius of a static black hole of that mass is roughly 12.3 million km, or 17.7 x the radius of our sun. That's roughly 1/3 the size of Mercury's orbit. You could put it in the center of our solar system, and not devour a single planet (though they would start orbiting a *lot* faster).

    Hold out your fist at arm's length. If you put the Milky Way's central black hole where our sun was, it would be roughly that big.

    Now, imagine trying to see something that size, which is perfectly dark, from 27,000 light years away and you'll understand how difficult it would be to directly image it.

    • by bcrowell ( 177657 ) on Wednesday January 18, 2012 @09:05PM (#38744292) Homepage

      I doubt that we're going to be directly imaging the event horizon for the central black hole anytime soon. [...] Now, imagine trying to see something that size, which is perfectly dark, from 27,000 light years away and you'll understand how difficult it would be to directly image it.

      Direct imaging of its event horizon is exactly what they're planning to do: http://arxiv.org/abs/0906.3899 [arxiv.org]

      • Well at least "angular resolution comparable to the event horizon". Comparable to the diameter of the black hole I guess which is the event horizon. If this is one pixel then I don't know what you can get from that .
        • Well at least "angular resolution comparable to the event horizon". Comparable to the diameter of the black hole I guess which is the event horizon. If this is one pixel then I don't know what you can get from that .

          You might get a pretty good view of the large-scale structure of the presumed infalling matter.

        • by dkf ( 304284 )

          Comparable to the diameter of the black hole I guess which is the event horizon.

          It's exactly the event horizon; you definitely can't see anything inside of that limit by any means from outside by its very definition.

      • by NixieBunny ( 859050 ) on Wednesday January 18, 2012 @10:28PM (#38744826) Homepage
        The telescope that they use is actually several radio telescopes capturing the same signal at the same time, in an observing mode called VLBI for Very Long Baaseline Interferometry. The data captured are correlated off-site (or in real time if they can build a trans-oceanic Gbyte/sec data link) to get a wave-by-wave signal match, producing interference fringes that permit the construction of a very high resolution image. These days, they store the GByte/sec data on a bank of hard disk drives and FedEx them to the correlator in Virginia.

        I happen to work on one of these telescopes, the Heinrich Hertz Submillimeter Telescope on Mt. Graham in Arizona. We have a hydrogen maser on site to produce a clock accurate enough to collect the data synchronously with other telescopes in other parts of the world.
    • by dissy ( 172727 )

      They're not imaging the event horizon, they're trying to image the accretion disk around the central black hole, and hoping they can see the event horizon's "shadow" against it. I doubt that we're going to be directly imaging the event horizon for the central black hole anytime soon.

      The telescope they are using is named "The Event Horizon Telescope"
      It is not being claimed anywhere that they plan to directly image the event horizon.

      This might surprise you, but the Hubble telescope was not designed and launched into space with the goal of taking pictures of Edwin Hubble either :P

      Now the James Webb Telescope on the other hand, that thing is run by a bunch of peeping toms for sure!

  • They've got a picture of it up on Wikipedia, but not for much longer!
  • by bcrowell ( 177657 ) on Wednesday January 18, 2012 @09:23PM (#38744400) Homepage

    It might be a bit of an oversimplification to call this a test of relativity.

    Relativity consists of special relativity (SR) and general relativity (GR). GR includes gravity.

    SR has been tested in many different ways to extremely high precision. Here [edu-observatory.org] is a summary of experimental tests of SR. Note that even if the faster-than-light neutrino result from CERN/Gran Sasso is correct, it doesn't necessarily conflict with SR. SR doesn't forbid FTL. It only forbids an object from being accelerated from a speed less than c to a speed greater than c.

    Here [livingreviews.org] is an article on tests of general relativity. A nice popularization of this kind of thing is the book Was Einstein Right? by Clifford Will. Although GR has not been as thoroughly tested as SR, it has been tested in many different ways. There is not really a heck of a lot of doubt that it's right in many ways. Alternative theories exist, but they are extremely tightly constrained by observation.

    We expect that Sagittarius A* is a black hole, and the definition of black hole basically means that it has an event horizon. If, contrary to everyone's expectations, it turns out not to have an event horizon, the most likely interpretation may not actually be that GR is wrong. It may actually mean that there is something wrong with relativistic particle physics. It's possible that the process of formation that we think leads to a black hole actually stops short of forming a black hole, and instead forms some other exotic object. There are various speculations about these things: gravastars, fuzzballs, quark stars, boson stars, q-balls... If we found out that Sgr A* was one of these hypothetical critters, it would be very exciting for the particle physicists, but it would not disprove GR.

    • by Black Parrot ( 19622 ) on Wednesday January 18, 2012 @11:39PM (#38745298)

      We expect that Sagittarius A* is a black hole, and the definition of black hole basically means that it has an event horizon. If, contrary to everyone's expectations, it turns out not to have an event horizon, the most likely interpretation may not actually be that GR is wrong. It may actually mean that there is something wrong with relativistic particle physics. It's possible that the process of formation that we think leads to a black hole actually stops short of forming a black hole, and instead forms some other exotic object. There are various speculations about these things: gravastars, fuzzballs, quark stars, boson stars, q-balls...

      IANAPhysicist, but AIUI:

      A fuzzball would be indistinguishable from a black hole, since it's a hypothesis about what's what inside the event horizon.

      A gravastar may also be indistinguishable (from outside), but I'm less sure about this.

      The others, I think, would still form black holes if they had the amount of mass inside the amount of volume required by the observations.

      Correct me if I'm wrong; I love learning about this stuff.

    • Note that even if the faster-than-light neutrino result from CERN/Gran Sasso is correct, it doesn't necessarily conflict with SR. SR doesn't forbid FTL. It only forbids an object from being accelerated from a speed less than c to a speed greater than c.

      That's just not true. SR forbids anything, even information [wikipedia.org], from travelling FTL because as a consequence of time dilation in non-FTL reference frames if you could travel or communicate FTL then you could create closed causal loops. Causality is one of the basic assumptions of SR along with relativity and constancy of the speed of light.

      Objects with mass can't be accelerated to the speed of light for a different reason -- because it would require infinite energy. So accelerating past c is obviously not p

  • Libera te tutemet ex inferis!

  • What If... (Score:4, Interesting)

    by mlauzon ( 818714 ) <mlauzon@gma[ ]com ['il.' in gap]> on Wednesday January 18, 2012 @10:22PM (#38744796) Homepage
    It turns out there is no black hole at the centre of the Milky Way?
  • Maybe they should check Uranus if they are looking for central black holes. I hear it might be supermassive.
  • That movie gave my gf (at the time) nightmares for a week...

    I hope this telescope is more successful than the ship of the movie!

  • I dont pretend to have any idea if this could be done. But when I saw the animation of the nearby stars swooping around the centre of the milky way... it was so beautiful. I support all attempts to image this area further. I for one wish them all the best luck in this endeavour.and cannot wait to see the results. Best luck u star gazers.
  • Yet we have thousands of photos of our galaxy in shades of cream, blue, pink and purple. In addition, much of the light we see of the Milky Way from Earth is blocked by dense dust. Therefore, we can only see 1,000 to 2,000 light-years in any direction...........more http://www.dbune.com/news/tech/10045-us-astronomers-say-they-have-discovered-the-milky-ways-true-colors.html [dbune.com]

You will lose an important tape file.

Working...