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Space Science

Supermassive Black Holes Not So Big After All 153

An anonymous reader writes "Supermassive black holes are between 2 and 10 times less massive than previously thought, according to new calculations published by German astrophysicists (abstract)."
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Supermassive Black Holes Not So Big After All

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  • but but (Score:4, Funny)

    by Dyinobal ( 1427207 ) on Thursday February 17, 2011 @10:19AM (#35232200)
    but they are still super massive right? If not that totally ruins most of my celestial bodies jokes.
    • by mangu ( 126918 )

      but they are still super massive right? If not that totally ruins most of my celestial bodies jokes.

      Not all of them, only the "yo momma so fat" jokes. The Uranus jokes are still in effect.

    • It will only effect geeks that tell and receive insults, because they are the only ones that will be able to reference this.

      So to all the people that don't read Slashdot : "Yo momma is so fat. If she gained another pound, she would collapse in on herself and become a black hole."
      • Re: (Score:2, Funny)

        by kencurry ( 471519 )

        It will only effect geeks that tell and receive insults, because they are the only ones that will be able to reference this. So to all the people that don't read Slashdot : "Yo momma is so fat. If she gained another pound, she would collapse in on herself and become a black hole."

        and then became uranus...

        • and then became uranus...

          Urectum is the name the planet Uranus was changed to in 2620 to avoid people making the "your anus" joke.

      • by funaho ( 42567 )
        Yo mamma's so fat, her event horizon IS the horizon!
      • You need some jargon in there to make it a real geek insult. How about "Yo momma's so fat the next Big Mac she picks up will increase her mass beyond the Chandrasekhar limit", then you could score some bonus points by throwing in something about electron degeneracy pressure.

      • Rearranged :

        So to all the people that don't read Slashdot :

        Errr, "null" ?

        It will only effect geeks that tell and receive insults, because they are the only ones that will be able to reference this.

        While it may or may not be true that "most geeks receive insults", it is also very likely true that most geeks don't notice many of the insults they receive. [grammar-nazi]"affect" here, not "effect"[/grammar-nazi]

        "Yo momma is so fat. If she gained another pound, she would collapse in on herself and become a bl

    • but they are still super massive right? If not that totally ruins most of my celestial bodies jokes.

      The downgrade to UltraClumpy should preserve your astronomical punch lines.

    • by Nyder ( 754090 )

      but they are still super massive right? If not that totally ruins most of my celestial bodies jokes.

      They like to call themselves "big boned".

    • Does this broad line region make my butt look massive?
  • Sheesh! (Score:5, Funny)

    by Anonymous Coward on Thursday February 17, 2011 @10:27AM (#35232304)

    You mean, they're only hundreds of millions to a billion times the mass of the sun, not several billion times the mass of the sun? Sheesh! Talk about phoning it in! Wake me up when they're serious about being 'super massive'!

  • Math? (Score:3, Insightful)

    by LocutusMIT ( 10726 ) on Thursday February 17, 2011 @10:28AM (#35232312) Homepage

    How can something be X-times less massive than something else? I can understand half as massive, or 1/10 as massive, but two to ten times less massive doesn't make any mathematical sense for a result that must be a positive number.

    • Re: (Score:3, Insightful)

      by ArcherB ( 796902 )

      How can something be X-times less massive than something else? I can understand half as massive, or 1/10 as massive, but two to ten times less massive doesn't make any mathematical sense for a result that must be a positive number.

      I agree. That pet peeve ranks right up there with "I could care less".

      Like nails on a chalkboard.

      • Or blood is thicker than water.

        I mean come on! if your gonna use a meme at least use it right.

      • I agree. That pet peeve ranks right up there with "I could care less".

        Like nails on a chalkboard.

        The phrase is "I couldn't care less". Indicating that I care so little for something that no matter what you tell me it's not going to make the subject any more insignificant. "I could care less" indicates that I care enough that my feelings on the matter could be swayed to become more apathetic than they currently are. Obviously there's a big difference, though I do hear an awful lot of people misstating it as you have posted.

        • *WOOSH*
          • *WOOSH*

            Perhaps, but in all honesty I hear that phrase misquoted more often than used correctly.

            • by SpeZek ( 970136 )
              It definitely went right over your head, but I see you could care less.
            • *WOOSH*

              Perhaps, but in all honesty I hear that phrase misquoted more often than used correctly.

              There is no 'perhaps' involved in this at all. The person you replied to was citing it as his own pet peeve. You wasted your pedantry.

        • Or, "I could care less" means I care so little, I could care less about this than anything else I'm supposed to care about.
        • Since the "whoosh" didn't explain it clearly enough: That's why GP called it a "pet peeve". Because it's a misuse of a common phrase.

          - RG>

      • I don't like it either, but both "I could care less" and "I couldn't care less" are valid.

        "I could care less ... but I'd have to really work at it ..." - ie: I don't really care enough to get worked up about it.

        "I couldn't care less ... even if I tried" - ie: I don't care at all.

        And 10 times less massive is the same as saying "an order of magnitude less", which makes sense. Same as double-entry bookkeeping ...

        Just look at "flammable" and "inflammable".

      • by Anonymous Coward

        The expression "five times smaller" gets nearly 1M hits on Google, you have quite an uphill battle! In fact you might want to reconsider whether you're wrong instead of the world.

      • by Anonymous Coward

        You confuse the adverb “less” with the preposition “less”. The adverb “less” means “to smaller extent” or “in lower degree”. The sense of “subtraction” applies only to the preposition (“gross income less expenditure equals net income”).

        This usage of “less” is symmetrical with that of “more”, except for the less/fewer distinction. Observe:

        You have two dollars. I have two more dollars than you. I have

      • by icebike ( 68054 )

        Me: Hello, I would like to order 10 bags of cement.
        Hardware Store: yes sir, we will deliver those today.
        Me: Wait, make that two times less bags.
        Hardware Store: But Sir, there is no such thing as a negative bag of cement.

    • Re:Math? (Score:4, Insightful)

      by mangu ( 126918 ) on Thursday February 17, 2011 @10:33AM (#35232382)

      How can something be X-times less massive than something else? I can understand half as massive, or 1/10 as massive, but two to ten times less massive doesn't make any mathematical sense for a result that must be a positive number.

      Don't worry, it's only you. Everybody else understood perfectly that they are now estimated to be between 10% and 50% of the former estimate. Or can you imagine any other reasonable interpretation for that?

      • Don't worry, it's only you.

        No, it's not. It's a ridiculous way to express things like that, and it's actually misleading. To say that something is ten times less massive means that you consider the thing to which it's being compared to already be not very massive (compared to what?). That leaves a bunch of implications dangling open and unanswered. Saying it's "a tenth the size" is far more appropriate, and doesn't imply anything about the larger item to which you're comparing it. If you mean to say that the ten-times-larger thing i

        • To say that something is ten times less massive means that you consider the thing to which it's being compared to already be not very massive (compared to what?).

          No, you are incorrectly parsing the statement. "X is ten times less massive than Y" is clearly comparing X to Y, finding the difference to be a ratio of ten, and specifying the sense to be that X is less than Y. There's no implication about the absolute massiveness of Y.

          There IS a very slim opportunity for ambiguity, but it's not the one you're suggesting. Because of the parallel structure to "X is ten kg less massive than Y" so, if one is not very perceptive, he might conclude that mass(X) = -9 * mass(Y

      • Everybody else understood perfectly that they are now estimated to be between 10% and 50% of the former estimate.

        So 10x less massive = n - (1/10)n

        2x less massive = n - (1/2)n

        and by extension:

        1/2x less massive = n - (1/(1/2))n
        = n - 2n

        If the terminology is used consistently, then that last step doesn't make sense. It also doesn't make sense how "ten times" translates to "one tenth", its inverse.

        - RG>

    • by msauve ( 701917 )
      Because "between 2 and 10 divide less massive" doesn't sound right.
    • Re: (Score:2, Funny)

      by Anonymous Coward

      "2 * less" == (x * -1 * -1);
      "10 * less" == (x * -1 * -1 * -1 * -1 * -1 * -1 * -1 * -1 * -1 * -1).

      Is my guess.

    • Re:Math? (Score:5, Insightful)

      by Xiph1980 ( 944189 ) on Thursday February 17, 2011 @10:38AM (#35232438)
      two times less massive: 1/2 * m
      ten times less massive: 1/10 * m

      Really, if you want to make it in the world out there, you've gotta get off of your high pedestal, and accept that the scientific world is only a small percentage of the "regular folk" out there. Theoretically, you're right, but practically, noone cares about theory so you're screwed.
      • Re:Math? (Score:5, Insightful)

        by Trepidity ( 597 ) <[delirium-slashdot] [at] [hackish.org]> on Thursday February 17, 2011 @10:57AM (#35232708)

        It's not even uncommon language in science, though maybe you'd be more precise when writing a paper. In this context, "times" is understood as colloquial shorthand for "by a factor of", and factors can be either multiplied or divided, depending on whether it's "greater" or "less" by that factor.

        The translation from "two times less massive" to "less massive by a factor of two" is pretty straightforward and easily understood...

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

          by mangu ( 126918 ) on Thursday February 17, 2011 @11:19AM (#35233034)

          The translation from "two times less massive" to "less massive by a factor of two" is pretty straightforward and easily understood...

          The real problem happens in the opposite direction. A star that's 200% as massive as the sun is smaller than one that's 150% more massive than the sun, but many people will give the wrong answer if asked.

          • Why use percentages in an intentionally confusing and inconsistent way like that?

            • by mangu ( 126918 )

              Why use percentages in an intentionally confusing and inconsistent way like that?

              I don't know, but people do it. When they say things like "n times more than", a slight variation in words might mean either (y = x * n) or (y = x + x * n). I'm not nitpicking, it can be very confusing.

              OTOH, when they say "n times less than" it always means (y = x / n), it's only the Slashdot anal-retentive trolls who find any problems about it.

        • Re:Math? (Score:4, Informative)

          by Mr_Huber ( 160160 ) on Thursday February 17, 2011 @11:26AM (#35233132) Homepage

          It's also a difficulty with language. In physics, mass and weight are two separate concepts. We have comparison words for weight: heavier and lighter. But we do not necessarily have the same comparison words for mass. So we're stuck with the English default construct of more massive and less massive. Sure, we could use lighter in this context and hope everyone understands we really are discussing the concept of mass, not gravitational attractive force to the local big rock, but most physicists dislike that imprecision.

      • Really, if you want to make it in the world out there, you've gotta get off of your high pedestal, and accept that the scientific world is only a small percentage of the "regular folk" out there. Theoretically, you're right, but practically, noone cares about theory so you're screwed.

        Scientific and mathematical language is precise for a reason, which is that both depend on long chains of rigorous reasoning, and ambiguity wastes the time of the reader at minimum. At worst, it renders the description unusable. This actually matters in science and math. For "regular folk" who just skim superficially from science as a form of entertainment, we could just as well make up something for all the difference it would make.

        Your complaint reminds me of the defensive "You know what I meant!" the dum

        • Hahahaha, you're funny!

          Besides you not knowing anything about me, about my education or success, you assume that I am a burger flipper at White Castle or something. You presume that my spelling and grammatical errors are indicative of my intelligence. Well, believe what you want, but by the time your skills in Dutch, German, French and English are as good as mine, please, be free to comment on my grammatical errors. You see, not everyone comes from the land of fatties and diabetics and has English as the
    • x^-2

    • Re: (Score:2, Informative)

      by Anonymous Coward

      The pattern "x as massive" isn't the same as the pattern "x times less massive". You understand the first pattern. Now you need to learn the second pattern.

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      Personally, I'm also bothered when I hear "5 times more". Is it 6 times as much or 5 times as much?

    • Re:Math? (Score:5, Insightful)

      by nedlohs ( 1335013 ) on Thursday February 17, 2011 @10:53AM (#35232660)

      Welcome to the English language, you will notice that it is not actually a branch of Mathematics.

    • Fucking Multiplicative inverses.... how do they work?

      • by radtea ( 464814 )

        Fucking music... how does it work?

        • Fucking moon... how did it get there?

    • by civex ( 1863950 )
      Isn't that aggravating? The holes are from 1/2 to 1/10 as massive. You _can't_ be 2 times less or 10 times less. Sheesh!
      • by osu-neko ( 2604 )

        You _can't_ be 2 times less or 10 times less.

        You can. However, only a fluent speaker of the English language will understand what you mean when you say that, as the transformation of that into mathematical language is not straightforward.

    • My tolerance for this sort of pedantry grows smaller by the day.

      • by osu-neko ( 2604 )

        My tolerance for this sort of pedantry grows smaller by the day.

        Yeah, my tolerance is ten times smaller than it used to be.

      • by nelk ( 923574 )

        My tolerance for this sort of pedantry grows smaller by the day.

        But how much smaller? 20%? 50%? How are we supposed to know how to correct you if you don't give us these details?

  • This shows that science is just a mass of arbitrary assertions.
    This abject, craven, flip flopping about face allows me to justifiably substitute my own preferred notions into the debate as fact.
    This effectively proves that global warming, vaccination, evolution, and all other liberal plots are bald faced lies.

    Its an outrage! If scientists can revise their theories based on improved evidence, science is untrustworthy claptrap that must be excluded from debate.

    • You are a bit too self-aware about it to not be joking; but it is a matter of continual puzzlement to me that so many people accord higher regard to an assertion made with certainty than to one made with explicit provision for updates in the face of new evidence.

      It's just a really weird defect.
      • by bunratty ( 545641 ) on Thursday February 17, 2011 @10:48AM (#35232562)
        Certainty in a position gives people a stronger reason not to believe competing ideas. It's basic cognitive dissonance. Let's say I prepared for aliens to visit and destroy the world on a certain day [wikipedia.org]. When that doesn't happen, I can either admit I was wrong or I am uncertain about whether these aliens even exist, or I can confidently believe that the aliens spared us because of our faith. It's easier to confidently believe that AGW is a big hoax than to admit the possibility that we're causing the climate to change. It's easier to believe that evolution is not real if it causes me to question my faith in the existence of God. People will do all kinds of mental gymnastics rather than admit a truth they find emotionally disturbing. Even the lamest excuse will do. The latest is the old "the science isn't settled" when there's the least little bit of uncertainty.
      • It's a simple fact that people are dumb.
    • I'd even push the thought further. Knowledge as a whole, is just a mass of arbitrary assertions. That means nothing I know can considered trustworthy! :'( At least Descartes' "Dubito ergo cogito ergo sum" allowed me to assert that I do exist. Unless...
    • Just wait until the mods eventually flip flop on their broken sarcasm detectors.

  • by Anonymous Coward

    We will colonize the Galaxy with our chemical rockets and frail bodies that give 10-20 years of useful life at best. How will this change our plans?

    • by osu-neko ( 2604 )
      It won't. It only affects the estimates of distant black holes. The one in the center of our own galaxy has a mass determined by much more reliable methods that aren't subject to the kind of error discovered here.
  • by ArhcAngel ( 247594 ) on Thursday February 17, 2011 @10:35AM (#35232408)

    Will MUSE release a followup called "Not So Supermassive - Black Hole"

  • Despite being less dense than before, I'm pretty sure they'd still crush us all into a singularity-sized monodimensional pin dot.
    • by Anonymous Coward

      I'm not so sure. My latest calculations show you could walk on the surface completeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee...

    • by Kronon ( 1263422 )
      Treating these as classical black holes, they would only be less massive, not less dense. Classical black holes have diverging density due to collapse of a finite mass to a singularity. If you propose that black holes have internal structure then it's reasonable to suggest that differences in density could result.
      • by Rich0 ( 548339 )

        Wouldn't the internal structure of a black hole vary with time - and not just trivially?

        After all, it takes from now until the end of the universe for something to fall into the event horizon of a black hole, from our perspective.

        Doesn't that mean that right now every black hole out there is just a neutron star with one extra electron an infinitesimal distance inside the event horizon radius? Sure, it will become a singularity - but from our perspective perhaps not before it evaporates.

        Now, from the perspe

  • I am sure there is a great joke here, but I am not witty enough to put it in words

    -1 Offtopic, I know.

  • by Taibhsear ( 1286214 ) on Thursday February 17, 2011 @10:56AM (#35232694)

    How would this relate to theories of dark matter? I don't know what formulas they use to determine this so would this lessen the necessity for dark matter or exacerbate the problem further (more dark matter than previously thought), if said formulas are accurate?

    • by osu-neko ( 2604 )

      How would this relate to theories of dark matter?

      It doesn't. Changing theories of how much of a galaxy's mass is or isn't in its central black hole have no impact on the estimates about of mass of the galaxy, much less the amount of mass in the universe, it only impacts where we think it's located.

  • 2 and 10, That's not a very good re-guess. I mean it's kinda like when they say the universe is between 10 - 20 billion years old. You need to be a lot more certain, I would give them 9-10 times but 2 - 10 is just to wide a range. It would be like me saying I'm anywhere from 1 to 100 years old and being fine with that range.
    • by osu-neko ( 2604 )

      You've completely misunderstood. They're not saying a particular black hole is 2 to 10 times smaller than thought, or that all black holes are 2 to 10 times smaller than thought, they're saying some estimates we've made are off by a factor of two, and some are off by a factor of ten, and others are at various places in between. It's like saying people in the audience are between 12 and 77 years old. That doesn't indicate uncertainty, it indicates the fact that the youngest member is 12, and the oldest is

  • This should say, "Supermassive black holes are now thought to be between 2 and 10 times less massive than previously thought..." Scientists would do everyone a favor if they dropped the formula "we used to think, but now we know". Appearing to have certainty about the newest scientific model gives the impression they are little different from the religious believer.

    I could have dismissed this as the reporting being at fault, but the abstract ends with "Knowing the rotational velocities, we can derive the ce

    • by c6gunner ( 950153 ) on Thursday February 17, 2011 @12:38PM (#35234124) Homepage

      Scientists would do everyone a favor if they dropped the formula "we used to think, but now we know".

      Kinda hard to drop something that's never been used.

      I could have dismissed this as the reporting being at fault, but the abstract ends with "Knowing the rotational velocities, we can derive the central black-hole masses more accurately; they are two to ten times smaller than has been estimated previously."

      Emphasis added. Hope that helps with your parsing problem.

    • by treeves ( 963993 )

      Moe: Why do you think so?
      Larry: I don't think. I know.
      Moe: I don't think you know either.

  • "That's heavy man"
  • by fermion ( 181285 ) on Thursday February 17, 2011 @11:16AM (#35232960) Homepage Journal
    Many around here complain that the quality of science reporting is really bad because reporters tend not to understand the science and tend to think that they have to simplify the results to what the common reader can understand. In the process the reporters use words that are interpreted differently by common people and scientists who understand the science, so communication break down.

    Then we do the same. The interesting results from this paper is a relationship between the spectra of the active galatic nucleus(AGN), which we infer to be a so-called black hole, the motion of the the AGN, and the geometry of the AGN. Given the inferred rotational velocity, the mass of central black-hole can be derived. If all this is true, the mass would be at most an order of magnitude less than previously thought. An order of magnitude correction is significant. It gives us something to test to confirm the assertions of the author. OTHO, I do not see that, in the absence of further work, these results are to be taken at face value that there is an order of magnitude discrepancy in the mass of these AGN.

  • by Mr_Huber ( 160160 ) on Thursday February 17, 2011 @11:23AM (#35233088) Homepage

    Well, it's nice to know that something in the Universe now sucks less.

  • Black hole masses of those measured from nearby systems where Keplerian velocities are resolved will not shrink.

  • "Gas can potentially corrupt results"

    Yes it can... especially on a first date.

  • There is no such thing as 2 to 10 times less, it's 1/2 to 1/10!! Leave times for things that are bigger, not smaller! I hate reading times and then having to stop and translate it in my head that they are saying something is less. It's like reading a string of double negatives! Are people really too stupid for simple fractions these days? Even on Slashdot, news for 'nerds'? </rant>
  • Muse has retitled their song "Still fairly large black hole"
  • Your mom thought they were pretty big, CmdrTaco.

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