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Giant Black Hole At Milky Way's Core Stays Slim 61

thomst writes "A team of researchers from Harvard and MIT announced at the 215th meeting of the American Astronomical Society a new theoretical model of how the super-massive black hole at the center of the Milky Way consumes gas from surrounding star clusters, based on a million seconds of observation by the orbital Chandra X-ray telescope. Astronomers had previously believed that the object, known as Sagittarius A* (pronounced 'Sagittarius A-Star') consumed only around one percent of the gases it stripped from the star clusters around it, but the new model reduces its consumption to 0.01 percent (i.e. — two orders of magnitude).'s uncredited reporter gets the story right, while's Andrea Thomspon clearly doesn't understand the mechanism behind the phenomenon (essentially, thermal conduction from the extremely-hot accretion disk heats the surrounding gas, causing it to expand, and thus move away from Sagittarius A*'s gravity well)."
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Giant Black Hole At Milky Way's Core Stays Slim

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  • by drainbramage ( 588291 ) on Wednesday January 06, 2010 @11:18AM (#30669766)

    Then it would be Sagittarius A* eh?

  • Harvard and MIT announced at the 215th meeting of the American Astronomical Society

    Does this mean there is a President of Astrophysics?

    • by Luyseyal ( 3154 )

      And how does this disprove the racecar on a train thought experiment []?


    • Naw, their society is an autonomous collective, specifically an anarcho-syndicalist commune. They take it in turns to act as sort-of-executive officer for the week but all the decisions of that officer have to be ratified at a special biweekly meeting by a simple majority, in the case of purely internal affairs but by a two thirds majority, in the case of more major issues.

      Hope that helps!

  • Well it looks like this sucks... a little. *cues CSI:Miami Theme music!*
    • Oh come on. You get a C for effort on that one. Watch and learn...

      Horatio, the star next to Sagittarius A was killed and only .01 percent of it's gasses were actually accreted!

      Well Calleigh, just because it's appetite sucks, that doesn't mean it's not guilty of *murder*...


      • Well Calleigh, just because it's appetite sucks,

        Mmmmmm, Calleigh.

        Mmmmm, appetite for sucking.

        My apologies to Miss Procter. I'm sure she's heard worse. But then, how do we know she doesn't have such an appetite?
  • So who cares? (Score:4, Interesting)

    by tetrahedrassface ( 675645 ) on Wednesday January 06, 2010 @11:27AM (#30669900) Journal
    So is this story about the black hole, or about the fact that one place got the story right, while another author got confused? Sounds like a hit job to me, and probably better ways to fulfill vendettas.. Just sayin'...
    • I agree, maybe a astronomy blogger death match is in order. I'm guessing that "'s uncredited reporter" is actually Slashdot's very own Anonymous Coward.
    • Re: (Score:3, Insightful)

      by thomst ( 1640045 )
      Nope. I personally don't know or care about Andrea Thompson at all. But her name was on the story, so I mentioned it. That's called "creditng the source."

      As for my story, it is, of course, about both things - the new theory about Sagittarius A*, and the reporting about the theory - because both are relevant to me.

      You're welcome not to care about either, though. Just try not to impute motives to other people without justification, lest you, yourself be judged a cynical troll with way too much t

      • It's useful to know which popular science sites get it right and which don't. I prefer so far, but I'm always willing to give a chance to other secondary sources, provided they know enough to accurately summarize what's published in Nature, Science, and other peer-reviewed but costly research journals.
  • 1 million seconds (Score:4, Informative)

    by qazsedcft ( 911254 ) on Wednesday January 06, 2010 @11:32AM (#30669978)
    A million seconds is about 11.5 days.
    • Just curious, does it mention if they were consecutive seconds? Or was this taken over the course of several months, with several recordings each night (because I imagine, even if the recordings were only at night, which is logical, and even if they were done over a good week, that still represents a very tiny portion of the black hole's existence, and any number of things could have happened in the span of one week's weeknights.)
  • by Sockatume ( 732728 ) on Wednesday January 06, 2010 @11:33AM (#30670016)

    Actually, the story does mention the correct mechanism ("It also creates pressure that helps some stellar winds avoid the black hole's gravitational grasp altogether."), but also a second one ("The conduction causes some of the heat in the gas to travel outwards, reducing the strength of the radiation that results from the black hole's consumption.") that sounds a bit odd. Physorg doesn't credit a reporter because they're printing a CfA-authored story (as evidenced by the "Provided by Harvard-Smithsonian Center for Astrophysics").

    • Physorg doesn't credit a reporter because they're printing a CfA-authored story

      Holy shit! I misread that as CIA... the mind boggles at the conspiracy theories that would cause...

  • I know this is slightly off topic, but in my opinion the words "Milky Way" and "Slim" should not be used in the same sentence.
  • This is your cue to come in and post,

    "I am Andrea Thomspon, you insensitive clod".

  • After reading that yawner of a story, I am SO FUCKING GLAD I never pursued astro research after that summer of my junior year in college.

  • by MadCow42 ( 243108 ) on Wednesday January 06, 2010 @11:51AM (#30670324) Homepage

    >> essentially, thermal conduction from the extremely-hot accretion disk heats the surrounding gas, causing it to expand, and thus move away from Sagittarius A*'s gravity well

    If there is a dense enough concentration of gas that thermal expansion (i.e. pressure) can keep it out of the gravity well, then is there enough density to actually call that an atmosphere? It's an interesting thought... although going from "atmosphere" to anything else (life, etc.) has about a billion hurdles in-between.

    I would assume that in the disc there is a range of concentration/pressure, but never thought it would reach/exceed our atmospheric pressure. That would be cool.


  • To Andrea Thomspon's credit, Astrophysics is very difficult. It's my guess that the source material (i.e. press release, article in a science journal, etc...) was neither well written or clearly explained.
  • So women tend to like chocolate and telling them that they are slim. Milky Way's are made out of chocolate. It is all becoming clear now.

    The Milky Way is on a diet because it is right after New Year's and after the holidays.

  • Eleven and a half days is a lot more understandable. Who wrote that, Star Trek's Data?

    Actually it's 11.574074074074074074074074074074 days, if Data's watching.

    • Maybe it was a tribute to Carl Sagan.

      "And the spiral galaxy was carefully watched for billions and billions of... microseconds."
    • by treeves ( 963993 )
      Probably it was written that way to suggest a million seconds of data acquired over many nights, maybe thousands, not in a week and a half. Just a guess.
  • I think I figured out WHY there are galactic voids. The voids used to full of Galaxies ie. "The Missing Mass" that no one could find. If a galaxy's black hole gets too big it triggers the collapse of the Galaxy in question into a violent Quasar and it disappears from this universe within a few million years. The Mass is then removed from this universe as it tunnels itself into a another universal where it expands into it's own "Big Bang". The mass that is constantly being removed makes it appear the e

    • Re: (Score:1, Informative)

      by Anonymous Coward

      The idea that there are "white holes" on "the other side" of black holes is pretty much without support.

      • but what if the white holes are in a separate universe?

      • The idea that there are "white holes" on "the other side" of black holes is pretty much without support.

        I'm pretty sure that even black holes are rather difficult to prove. Seriously, the center of the galaxy is awfully dense. I'm sure the science is rigorous but I'm sure other phenomenon can explain this observation. Guess, I'll have to get my astrophysics books out.

  • The discovery that black holes can reduce their gas consumption of two orders of magnitude should help car makers to build better SUVs.
  • paper (Score:5, Informative)

    by bcrowell ( 177657 ) on Wednesday January 06, 2010 @12:45PM (#30671190) Homepage
    Here [] is the scientific paper.
  • by Anonymous Coward

    Seriously. How can you skip a joke like that? It's reaching out and grabbing you, pulling you in to never let go and never let anything escape.

    PS: How much more do I have to type to get past the lameness filter?

  • by digitalgiblet ( 530309 ) on Wednesday January 06, 2010 @12:50PM (#30671270) Homepage Journal

    >"Sagittarius A* (pronounced 'Sagittarius A-Star')"

    So... it isn't a star but they call it A-Star?

    Perhaps "The Saggitarius Object Formerly Known As A-Star"...

    • by Ogive17 ( 691899 )
      It's better than "Sagittarius Ao" (pronounced Sagittarius A-hole)
    • by Xtravar ( 725372 )

      The star is meant to refer to the asterisk in the name - not to describe the object with the name. Or are you trying to make a cute joke?

      • I don't know if it is a cute joke or not, but I hope most folks recognize it as a joke...

        I find it funny that the stated pronunication will forever make it sound to listeners like something it isn't (but something very closely related). Pronouncing the asterisk as "star" wouldn't be funny in any other context. Throwing "A" in there fairly guarantees that the speaker will have to explain, as in "Sagittarius A-Star which is not a star."

        So whether or not you think it is cute is up to you since that is a subjec

        • by Xtravar ( 725372 )

          From my impression of astronomers, they probably relish in the confusion and consider it a hilarious in-joke.

  • Perhaps someone can answer this question:
    Will there ever be a Fred A*?

  • Is that CNN's Andrea Thompson who was on Babylon 5 []? You'd think she'd know about thing or two black holes.

    • by rotor ( 82928 )

      Being on a science fiction show implies you know something about science? Since when?

  • Was I the only one who read that first as:

    "...known as Sagittarius A* (pronounced 'Sagittarius A-Hole')...." Made a lot more sense when they talked about the accretion disk around the black-hole...

  • Take look at this: [] Haramein, who has spent his lifetime researching fields of physics from quantum theory to relativistic equations and cosmology, will lead you along a fascinating discussion geared to a layman's understanding of the fundamental nature of the universe and creation that includes black holes, gravitational forces, dimensions, and the very structure of space itself - all of which are integral parts of his now-complete Unified Field Theory.
  • It's eating a Milky Way the size of a galaxy and it stays slim? Must have a terrific metabolism.
  • "known as Sagittarius A* (pronounced 'Sagittarius A-Star')" Oh, horse puckey! I did radio astronomy for a lotta years. Most folks refer to that source as "Sag-A", although a few folks tried "Saj-A".
  • This is why exercise is good for you, people. Look at all the stuff its eating and it still manages to stay slim.

"No, no, I don't mind being called the smartest man in the world. I just wish it wasn't this one." -- Adrian Veidt/Ozymandias, WATCHMEN