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Space Science

Massive Black Hole Devours Star 77

H3xx writes "Astronomers have observed a black hole shredding a star and sending a powerful beam of energy toward Earth. When it was first observed on March 28th by the Swift spacecraft, it was thought to be the implosion of an aging star, but is now believed to be the result of a star wandering too close to a black hole, imploding and converting 10% of the star's mass into gamma radiation. The energy burst is still visible by telescope more than two-and-a-half months later, the researchers report in the journal Science."
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Massive Black Hole Devours Star

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  • by blair1q ( 305137 ) on Friday June 17, 2011 @03:37PM (#36479484) Journal

    From TFA:

    But this event, first spotted on 28 March 2011 and designated Sw 1644+57, does not have the marks of an imploding sun.

    More like it got ripped apart. Shredded. As TFA's headline said.

    The summary confused me, since pulling mass away from a star would remove the mass that contributes to implosion (which occurs when the continuous explosion within it slows to where it can't keep the star inflated enough and the density gets low enough for implosion to begin, leaving a neutron star or a black hole). But TFA straightened it out.

    • Is that to say that the black hole by shredding apart the star, created another black hole, probably residing in side the first one, seeing as it ate up the star??

      • by blair1q ( 305137 )

        No, it's saying that it could not, because it's stripping matter away, preventing formation of a black hole or neutron star.

        • Eh, the star got shredded into the accretion disk swirling around the central blackhole, but what we really observe here is the jet of matter beaming from the pole of the black hole. From that far distance we can only see it because the black hole is oriented towards us, so the relativistic jet is pointing directly in our direction. A rare alignment or a rare object, that is why it is so interesting.
  • How far away is this spectacle? Aren't gamma rays harmful?

    • Nearly 4 billion light years.

      • by Skapare ( 16644 )

        So, then, does this set a record on /. for the oldest "old news" story?

        • No, the news about the Plank Telescope [wikipedia.org] have that record already.

        • I would think that articles concerning the Big Bang would predate the 4 billion years of this story, so probably not. If you consider our past discussions about multiple universes, oscillating universes, and so forth, it becomes even more muddy. I personally would like it just fine if Slashdot managed to make it no more than a week behind the headlines on other sites, versus the months to years that we get sometimes around here. Still, there is no other site on the Internet besides Arstechnica that has the

    • Re:Harmful? (Score:4, Interesting)

      by boristhespider ( 1678416 ) on Friday June 17, 2011 @03:45PM (#36479610)

      Redshift of 0.3 or so. Corresponds to a luminosity distance of almost 2 gigaparsecs. That's pretty far away.

      Also, those gamma rays are all observed above the atmosphere. Interesting and totally off-topic aside, gamma ray bursters were only observed when we started putting military satellites in orbit to check on nuclear development. There were all these high-intensity sources around, leading to an investigation as to whether the Soviets had any new technology. Eventually it was determined that, no, they didn't and that these sources were extremely far away.

      • by osu-neko ( 2604 )

        Either that, or the Soviets managed to develop intergalactic weapon systems. ;)

        Yeah, we probably would have noticed... probably...

    • by danlip ( 737336 )

      No, I'm pretty sure they give you superpowers.

  • This happened almost four billion years ago. :-/

    • Funny, but not really accurate. The concept of an absolute sense of time doesn't make sense when we're talking about objects so far away.
      • well, true, but i can certainly establish a meaningful measure. that thing's in our past light-cone, so it's not like it's separated by spacelike geodesics or anything. what they did in the article itself was to use the luminosity distance to say how far away it is. it's not a big jump from there to a time.

        it's the same as saying the universe is 13.7 billion years old. it is, if you choose the right coordinate system and are careful enough about how you define it.

    • For /. that's pretty close to real time.
  • Massive black **** devours ****
  • by Anonymous Coward

    Pics or it didn't happen!

  • FTFA:

    the star becomes elongated, first spreading out to form a "banana shape" before its inner edge - orbiting faster than the outer edge - pulls the star into a disc-shape that wraps itself around the hole.

    At this point, can fusion even occur at the core of the star? If not, can it even be considered a star once it's matter has been wrapped around a black hole? At what point do we stop referring to it as a star and just consider it part of the black hole's accretion disk. I suppose it really doesn't make a difference what it's called though, since it won't be around for very long.

    • Re: (Score:3, Funny)

      FTFA:

      the star becomes elongated, first spreading out to form a "banana shape" before its inner edge - orbiting faster than the outer edge - pulls the star into a disc-shape that wraps itself around the hole.

      At this point, can fusion even occur at the core of the star? If not, can it even be considered a star once it's matter has been wrapped around a black hole? At what point do we stop referring to it as a star and just consider it part of the black hole's accretion disk. I suppose it really doesn't make a difference what it's called though, since it won't be around for very long.

      When you eat chicken, when does it stop being chicken and begin being you? Mind-blowing, huh?

    • by blair1q ( 305137 )

      If the fusion has stopped because the tidal force from the black hole is relieving the gravitational pressure between the star's atoms, it's no longer a star. It's now the gas-giant formerly known as the star, soon to be the accretion disk.

      But you can still safely say "the black hole shredded the star", because nothing else could.

  • I'm still looking for diligent answer to my StackExchange question: http://physics.stackexchange.com/questions/8294/how-much-of-a-star-falls-into-a-black-hole [stackexchange.com]

    Arbitrary masses for the star and black hole should be fine, as you should be able to obtain a percentage of the star that is "DEVOURED!!11" and then create a line chart of the behaviors of stars and black holes with varying masses.

    This seems important just to know, but also to make predictions for the Black Hole model.

    Then again, I'm too dumb to answe

    • by osu-neko ( 2604 )
      I'd be suspect of any answer anyone gives. The event was too far away, and we didn't see the star in question beforehand, so even after we determine how much mass was blasted away in the jets or converted to gamma rays, we have no way of determining what percentage of the original amount that is, since we don't know the original amount. Any answer you get won't help make predictions or refine models, because they'll be obtained by using a model to try to determine the original mass based on how much we sa
    • by blair1q ( 305137 )

      According to TFA, all but 10%. Probably some small amount gets blown away by various processes that accelerate particles to near-light speed, but we're talking about a gravitational field capable of sucking down a star like a pan-dimensional soda straw. Anything with remaining rest mass is getting drained, eventually.

      • by earls ( 1367951 )

        What a wonderful coincidence to look foolish. But note the quote "10% of its mass is turned into energy and radiated as X-rays" so 10% is X-rays, but doesn't speak to the rest of the spectrum.

        • by blair1q ( 305137 )

          The rest of the spectrum is, if not negligible, then somewhat less significant than the X-rays.

          The distribution is not flat. It will have a big hump peaking in the x-rays and long tails above and below.

  • "sending a powerful beam of energy toward Earth."

    Perhaps I'm being pedantic about word choice here - surely a first for /. - but a "beam" of energy implies to me that the energy is narrow and focused, and that description made me think that something came out aimed at Earth (though not, of course, by any deliberate agency.) The original article uses the word "burst" which seems far more appropriate for the kind of energy release its talking about.

    • Re:"beams" of energy (Score:5, Informative)

      by boristhespider ( 1678416 ) on Friday June 17, 2011 @04:11PM (#36479924)

      generally black holes eject along beams from their poles. if one of those beams is pointing towards earth we get a big flash; if it's not we don't see as much.

      it's much the same with pulsars. the standard model is that they're neutron stars emitting extremely focused radiation from their poles.

      • Truth. And I was interested in whether this was the case here (and we were therefore extremely lucky to be able to observe the event) so I went back to the linked article. It too isn't terribly clear, but it uses the term "burst" fairly consistently, which would imply a non-directional release of energy, at least to me. Of course, that's also trusting someone to have gotten the semantics right, and I don't have much faith in modern science press, but I was too lazy to follow a second set of links to the

        • The full paper's here: http://arxiv.org/abs/1104.3356 [arxiv.org]

          I skimmed it earlier but I don't know if you'll get a better answer from the paper -- they're cautious and they're presenting their results and suggesting a few models (and pointing out that it's strongly identified with the centre of the host galaxy and most likely a star falling into the central black hole) but they're not doing any firm models.

          I believe (though it's not my field so I might be very out-dated; I learned about these at university and that

  • Not really big news as in major political events but things like this I find fascinating. Extremely large objects doing something that covers a noticable portion of the galaxy (fortunately our solar system is quite far away or we'd all be toast, literally). It kind of makes you wonder of the vast amount of energy involved, how did it all began and where will it end. Meanwhile all you and me puny earthers bitch and moan of all kinds of crap that really don't impact much beyond the surface of this third rock
  • So they've finally found a Black Hole Sun?

  • I'm assuming this this powerful beam of energy is an alien transmission which roughly translates to " You're next. "
  • ULTIMATE vor (the universe episodes)

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