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Space Science

Hubble Finds Double Einstein Ring 168

Einstein Duble brings us news that astronomers using the Hubble Telescope have discovered an extremely rare double Einstein Ring. Occasionally, galaxies or other bright objects are located in such a way that they are behind another galaxy when viewed from Earth. When light from the further galaxy passes a sufficiently massive closer galaxy, the path of the light is bent inward from all sides, creating a "ring" effect. In this case, not one, but two galaxies are directly behind the foreground galaxy, so the gravitational lens produces two distinct rings. Quoting Presscue: "The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped. In addition, the geometry of the two Einstein rings allowed the team to measure the mass of the middle galaxy precisely to be a value of 1 billion solar masses. The team reports that this is the first measurement of the mass of a dwarf galaxy at cosmological distance (redshift of z=0.6)."
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Hubble Finds Double Einstein Ring

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  • by mastershake_phd ( 1050150 ) on Thursday January 10, 2008 @09:04PM (#21993650) Homepage
    This is a prime example of the kind of useful knowledge that can be gained with projects like Hubble.
    • by pilgrim23 ( 716938 ) on Thursday January 10, 2008 @09:09PM (#21993708)
      Proving Einstein's theory was always been about getting a little behind as it were. The solar eclipse of May 29,1919 was the first confirmation of this. And, this new discovery is much like the 191 observation only writ large, one might say glactic large.
      • by caramelcarrot ( 778148 ) on Thursday January 10, 2008 @09:27PM (#21993856)
        Given that they are only vastly different scales, it is important - there is still uncertainty as to how gravity acts on extremely large galactic scales.
        • Extremely large scales is right. I guffawed when I read "precisely one billion solar masses".. like there are exactly a billion stars that mass precisely 1 solar mass each, or 500 million at .500000 solar masses each..
          • I hope this isn't a troll...

            They are saying that the total weight of the galaxy is 1 billion solar masses. They probably don't have it down to the gram, but an accuracy of 1 solar mass would be a huge accomplishment.

            It's kind of like when someone says that their mass is equal to X kilos, they don't mean that they are composed of X weights stored in France.
    • by Anonymous Coward on Thursday January 10, 2008 @09:48PM (#21994012)
      If you're truly Libertarian, Hubble is exactly the sort of thing you'd be against having the government fund.

      C'mon, homefry. Walk the walk if you're gonna talk the talk.
      • by mastershake_phd ( 1050150 ) on Thursday January 10, 2008 @10:15PM (#21994202) Homepage
        If you're truly Libertarian, Hubble is exactly the sort of thing you'd be against having the government fund.

        C'mon, homefry. Walk the walk if you're gonna talk the talk.


        Some Libertarians might be against funding things like Hubble. I personally am more concerned with personal freedom, and a balanced budget. Private industry isn't going to do certain things, Hubble is a prime example. The last thing this country needs to do is cut scientific research.
        • I agree, but... (Score:1, Interesting)

          by Anonymous Coward
          I've seen plenty of Libertarians that don't want the government to fund much of anything, ever, because "taxation is theft" or something like that.

          I'm glad to see that there are at least a few veins of common sense among the Libertarians, though, because the extreme sort are the most noisy.
          • Re:I agree, but... (Score:4, Insightful)

            by SQLGuru ( 980662 ) on Thursday January 10, 2008 @11:04PM (#21994614) Homepage Journal

            the extreme sort are the most noisy
            The same could be said of those of any persuasion......(political, religious, etc.)

            Layne
          • by sconeu ( 64226 )
            Libertarians run the gamut of the libertarian spectrum, just as Dems and GOP'ers run the gamut of the so-called liberal and conservative spectrums.
            • Libertarians run the gamut of the libertarian spectrum,

              What libertartian spectrum? Libertarianism is cut and dried. Strong property rights, no coercive government, free association, that's it.

              Maybe they aren't libertarians but some other form of anarchist. I'm sick an tired of libertarianism co-opting every form of anarchism as if they invented it. Libertarians that believe in government funding of anything aren't libertarians, and could be considered anarchists only by a large stretch of the definition. You don't get to redefine words to suit your personal ph

              • by sconeu ( 64226 )
                Not necessarily. Libertarians believe in the free market.

                In my opinion, where there isn't a free market (abusive monopoly, natural monopoly), some form of regulation is required. It should be the minimum necessary, of course, though.
                • by spun ( 1352 )
                  Libertarians don't believe in the possibility of abusive or natural monopolies. Only the government makes monopolies, and there's no such thing as market failure. If you believe in government intervention in markets at all then you don't believe in absolute property rights, and therefore are not even close to being a libertarian.

                  Although, I have to admit, I'm happy that a bunch of non-libertarians with some understanding of real world economics are cop-opting libertarianism. But you might want to take a loo
          • Taxation is theft. It is true that it isn't exactly optional but the benefits are enormous. Just look at the advances that came from tax-funded military and scientific projects that make our lives better.
          • I'm glad to see that there are at least a few veins of common sense among the Libertarians, though, because the extreme sort are the most noisy.

            Libertarians run the gamut from Ayn Rand worshipers to people that are merely fiscally conservative and socially liberal. The problem is that with a system that's only balanced with two parties, the moderates have to choose - and end up labeled as "neo-liberals" or "pro gay marriage conservatives" - while the reputation of the term "libertarian" ends up being se

        • Re: (Score:3, Interesting)

          by porpnorber ( 851345 )

          Personal freedom, sound economic policy, measured intervention in things that won't look after themselves - isn't this what we used to call 'Liberalism'? All the Libertarians I have encountered labour under the delusion that they are universal experts and that nobody but them (least of all people with actual domain-specific training!) should be doing any resource allocation. They don't want to fund street repairs - in case someone else uses tarmac they helped pay for - let alone science. Certainly a total f

          • So you met some kooks who identify themselves as 'libertarians'.... and you believed them?

            Look, you can be for cutting down the federal government to a manageable level and that doesn't mean that you would prefer that 100% of the current duties of the federal government to be eliminated.

            Though it is a convenient bit of ammunition. Take the most radical element that ever claimed to be of the movement and use them as a strawman for the entire movement.
            • by Roxton ( 73137 )
              The "liberalization" of Libertarianism is a recent phenomenon. Libertarianism got its popularity from the nigh-mathematical rigor of it's ability to give simple (bad) answers to hard questions. One of the biggest campaigns of the Libertarian party was Carla Howell running for Senate in my home state of Massachusetts. She was a "kook," as you might describe her. (I campaigned for her, but I was a stupid undergrad.)

              That said, the recent developments in Libertarianism are promising. I wouldn't vote for hi
            • by spun ( 1352 )
              You can't be a libertarian and be for anything less than getting rid of everything but the military. You don't get to redefine existing political movements to suit your personal philosophy just so you can go by a rebel moniker like 'libertarian.' There is a whole spectrum of existing political labels for you to choose from, don't bend one to fit you just because it's hip. No one is taking the most radical elements of libertarianism and using them as a strawman. We are taking libertarianism as it is official
            • So you met some kooks who identify themselves as 'libertarians'.... and you believed them?

              Yes, well, the 'kooks' in question actually seem to identify themselves as the Libertarian Party of Canada. So I guess I did believe them, yes. The fact that they are kooks—that was my point.

          • Re: (Score:3, Interesting)

            by mi ( 197448 )

            Personal freedom, sound economic policy, measured intervention in things that won't look after themselves - isn't this what we used to call 'Liberalism'?

            Ha-ha... Those are universal values. The political distinction depends on what you call "personal freedom", what is sound economic policy, how you measure the intervention, and which things you identify as incapable of "looking after themselves".

            "Liberalism" in America tends to consider free health care (at someone else's expense) an inalienable right,

            • (A quick and pointed but somewhat facetious response, more later if possible...)

              It sounds to me as if your main objection is to being made to do things at gunpoint. How curious, then, that disarming society is not item #1 on the agenda! I would certainly agree that an armed person is without moral authority, but do you mean it, I wonder?

              • by mi ( 197448 )

                It sounds to me as if your main objection is to being made to do things at gunpoint. How curious, then, that disarming society is not item #1 on the agenda!

                Maybe, it is because I never faced a gun of a fellow American? Only that of the Government...

                • Maybe, it is because I never faced a gun of a fellow American? Only that of the Government...

                  This is interesting in another way. I've thought for a long time that you guys need to take back your government. It seems from your words that you yourself no longer even conceptualise them as Americans, much less your representatives! From your earlier post it really does seem as if you are not defending a political ideal so much as complaining that the present American implementation of government sucks—an

      • by hyfe ( 641811 ) on Thursday January 10, 2008 @11:53PM (#21994938)

        If you're truly Libertarian, Hubble is exactly the sort of thing you'd be against having the government fund.
        Being against spending money on a project doesn't mean you're not allowed to acknowledge its positive sides.

        Seriously, I hate this sort of thing. Any proposal has good and bad sides. When you're making a decision you count them and weigh them against eachother. Then you make a decision. Obviously, he values 'really free market' really highly, but that doesn't mean he's not allowed to acknowledge the cases when there are more cons to his approach than usual.

        Acknowledging arguments and still making a decision is a sign of intelligence. Trying to force somebody else to make false choices, or attributing false opinions to them is stupid.. and way too bloody common.

        • Acknowledging arguments and still making a decision is a sign of intelligence.

          Definitely! But it's not necessarily Libertarian®.

          Trying to force somebody else to make false choices, or attributing false opinions to them is stupid.. and way too bloody common.

          Hey, nobody forced mastershake_phd to put that in his signature. If someone's going to self-label, anyone else is free to call them on it IMO. It's not like the signature said "Intelligent Pragmatic Political Discussion Forum."

          • by hyfe ( 641811 )

            Hey, nobody forced mastershake_phd to put that in his signature. If someone's going to self-label, anyone else is free to call them on it

            So, in order to be allowed to be intelligent and pragramatic without anyone complaining you have to hide your political affections?

            .. that does actually makes sense. I'm very convinced 'eek, he said something intelligent and pragmatic, kick him out!" (translated to political speech) has happended lots of times in lots of different political parties all over the world.

      • So disagreeing with one thing makes that person a non-Libertarian?

        Thanks for illustrating exactly what's wrong with American politics today.

        "Don't you dare disagree with the Party position."
      • by notque ( 636838 )
        "truly libertarian"

        So you mean Libertarian Socialism, or Anarchism. That wouldn't make you necessarily against Hubble Research.

        Oh.. You meant Right Wing Statism?
    • Seriously, I'm not being hostile with this question. Is your life better for knowing the precise mass of a galaxy which no human will ever visit? I could go out and mass a stone in my back yard rather precisely with a calibrated instrument right now -- that would advance The Sum Of Human Knowledge, insofar as nobody had ever determined the approximate mass of that particular rock before -- but is that knowledge *useful*?
      • by IndustrialComplex ( 975015 ) on Friday January 11, 2008 @08:52AM (#21997612)
        The measured mass of a galaxy useful? On its own, maybe or maybe not. Yet through this fortunate alignment we were given the chance to get information that, for lack of a better word, helps us 'calibrate' our astronomical tools.

        The universe is understood by using phenomenae like this to test our theories and provide a sort of astronomical 'yard stick' by which we can measure other objects. Objects that without this yard stick would be less well understood. One discovery is built upon another until, one by one, they form the sum of our understanding.

        So why not go out and measure the mass of that little rock in your backyard? Wouldn't it be amazing to discover that it had a density of 19.3 g/mL?

      • by Martian_Kyo ( 1161137 ) on Friday January 11, 2008 @08:58AM (#21997660)
        I am sure some people wondered in 1600s 'why is that newton guy researching gravity he is such a fool, I know if i drop an apple it falls. What does it matter how fast it falls, that won't help my crops grow.'
        There is no useless knowledge. There is knowledge we don't know how to use yet but no useless knowledge. Time will show, determining mass of a galaxy might turn out to be an essential calculation 300 years from now on, given civilization continues to evolve until then.
        • Re: (Score:2, Funny)

          by Anonymous Coward

          There is no useless knowledge.
          Have you seen these "celebrity magazines"?
  • by IdahoEv ( 195056 ) on Thursday January 10, 2008 @09:10PM (#21993720) Homepage
    One of the cool implications becomes clear if you realize this means our galaxy is the 4th galaxy in a line with these three. To someone standing on a planet in that backmost galaxy, 11B Ly away:
        * The one that's the "foreground galaxy" to us would be the inner ring.
        * The one that's the "first ring" to us would be the foreground galaxy for them and ...
        * The Milky Way would appear as the outer ring!
    • by Pedrito ( 94783 ) on Thursday January 10, 2008 @09:19PM (#21993796)
      One of the cool implications becomes clear if you realize this means our galaxy is the 4th galaxy in a line with these three. To someone standing on a planet in that backmost galaxy, 11B Ly away:

              * The one that's the "foreground galaxy" to us would be the inner ring.

              * The one that's the "first ring" to us would be the foreground galaxy for them and ...

              * The Milky Way would appear as the outer ring!


      Actually, that's not the case. I'll give you a hint. The reason is because of something the guy these rings are named after, figured out. These galaxies aren't aligned. They just look that way from our perspective. From the other direction, it's extremely unlikely these 4 galaxies ever aligned, as odd as that sounds.
      • Indeed, there aren't aligned. Which won't defer an idiot astrologer to make some prediction over the event of course.
      • Re: (Score:2, Insightful)

        If the galaxies look aligned from our perspective, they will look aligned from theirs. The inverse path
        of the light will be exactly the same since the path is dictated by the perturbation of spacetime.
        • by rewt66 ( 738525 ) on Thursday January 10, 2008 @09:40PM (#21993956)
          These things line up in space-time as follows: Galaxy 1 is on the line 11 billion years ago, galaxy 2 is on the line 6 billion years ago, galaxy 3 is on the line 3 billion years ago, and the Milky Way is on the line right now.

          This does not mean that the reverse is true. It does not mean that there is a line that the Milky Way was on 11 billion years ago, and galaxy 3 was on 8 billion years ago, and galaxy 2 was on 5 billion years ago, and galaxy 3 is on now. Why not? Because galaxies move.

          Still, even if not technically correct, it was a really awesome thought by the OP...
          • by Loki P ( 1170771 ) on Thursday January 10, 2008 @10:51PM (#21994496)
            And the other problem is the masses of all the galaxies are different. The dwarf galaxy wouldn't act as a lens for them in the same way that the massive galaxy does for us.
          • True. But if they are moving at the same speed there seems a good chance they would be lined up the other way. However not on the same line. It would be a line at the reverse angle to the hypothetical centre of the big bang.

          • Re: (Score:2, Funny)

            by Tablizer ( 95088 )
            These things line up in space-time as follows: .... This does not mean that the reverse is true. It does not mean that there is a line that the Milky Way was on 11 billion years ago, and galaxy 3 was on 8 billion years ago, and galaxy 2 was on 5 billion years ago, and galaxy 3 is on now. Why not? Because galaxies move.

            The communications delay is gonna make online gaming with those guys a bit cumbersome.
                   
        • No, they won't looked aligned.

          You're forgetting that light travels at a finite speed.

          Galaxy 1 emitted light 11 bya which interacted with galaxy 2, 3 and now shines on Earth.

          There is no "reverse path" for light from the Milky to take.
        • Re:And to them, we are the ring (Score:0, Troll)

          If the galaxies look aligned from our perspective, they will look aligned from theirs. The inverse path
          of the light will be exactly the same since the path is dictated by the perturbation of spacetime.


          I fail to see how this might be modded Troll. As for the statement, however, it doesn't work both ways - An Einstein Ring or Einstein Cross is not a discreet feature in space, it's an event similar in principle as an eclipse or occultation, and just as ephemeral
        • Bad moderator - no cookie!

          This isn't "insightful" because it's factually incorrect, and it's isn't "troll" because he isn't trying to incite or annoy anyone. If you think it's modded up too much, use "overrated".

      • Re: (Score:3, Interesting)

        by porpnorber ( 851345 )
        In your terminology, is there any circumstance under which objects in relative motion can be said to be 'aligned'? While I agree that relativistically speaking alignment isn't generally symmetric, I would have thought that this was exactly the situation in which one would have used the word - despite their limited speed, photon paths are the best 'lines' we have.
    • by EmbeddedJanitor ( 597831 ) on Thursday January 10, 2008 @09:31PM (#21993880)
      And (s)he's got a really big ruler!
    • by dafradu ( 868234 )
      Thats why its called relativity, Einstein :p
  • This seems like it would be a good opportunity to conduct the double slit experiment on a cosmic scale.
  • Extemely Rare? (Score:3, Insightful)

    by tomhath ( 637240 ) on Thursday January 10, 2008 @09:25PM (#21993838)
    It seems to me that there must be lots of Double Einstein Rings out there, probably millions of them. We're just not standing in the right place to seem most of them.
  • by MegaMahr ( 788652 ) on Thursday January 10, 2008 @09:42PM (#21993968) Homepage
    As the double ring they found around Uranus [nationalgeographic.com]
  • Whew! (Score:4, Funny)

    by mapmaker ( 140036 ) on Thursday January 10, 2008 @09:42PM (#21993972)
    I was afraid it was a trick to make me click on a link to goatse.cx guy.
  • My first thought was they filmed intergalactic wrestling with the Hubble.
  • <dreamy>It's real??</dreamy>
  • by numbware ( 691928 ) <justin@justinjacobs.com> on Thursday January 10, 2008 @10:11PM (#21994188) Homepage
    Brannigan: "What the hell is that thing?"

    Kif: "It appears to be the mothership"

    Brannigan: "Then what did we just blow up?"

    Kif: "The Hubble Telescope"
  • ...that this will enable them to defeat Dr. Robotnik by the end of the next level.

    Chris Mattern
    • And without the peanut gallery comments about "what a waste of taxpayer money" (even though this particular work is IIRC privately funded), and "gee, why not give up doing astronomy and put those bright boys to work fixing the homeless problem in New Orleans?" (Paraphrasing, but seriously, that's what one comment said.)

      TFA was cool, but those comments really depressed me. Sadly, most people still don't understand that their cell phone and their GPS receiver and a half million other things we take for gran
  • "Ah, so that's where I left those."
  • Ba dum bum (Score:5, Funny)

    by Dachannien ( 617929 ) on Thursday January 10, 2008 @11:15PM (#21994692)
    Additionally, the astronomers' significant others are annoyed at them for ruining the coffee table by not putting Eincoasters under their Einsteins.

  • by InterGuru ( 50986 ) <(moc.urugretni) (ta) (dhj)> on Thursday January 10, 2008 @11:22PM (#21994744)

    Bubble, bubble, toil and trouble
    Hubble finds an Einstein double

    Give a shivering man a lit match and it will warm him for a few minutes.
    Set him on fire and it will keep him warm for the rest of his life.

  • Who is this Duble brings us news of hubble finding double?
  • odds of this (Score:3, Insightful)

    by v1 ( 525388 ) on Friday January 11, 2008 @12:03AM (#21994992) Homepage Journal
    for this to occur requires four galaxies to be very close to being colinear, and we have to be in one of the endpoints. Looking at the picture though there are several galaxies visible so I suppose they have quite a few to look at for this. I wonder just how rare it is? As in, is this the first one discovered? I'd asume if there were any other known double E rings it would have been mentioned in TFA. Hard to say how rare something is when you only have one of them to go by.
    • by v1 ( 525388 )
      The article mentions "Einstein Ring" but that's just the visual effect. The actual gravitational lens pair is a "Solan Lens", and was found by a group looking for the single lensing pair variety. http://arxiv.org/abs/astro-ph/0511453 [arxiv.org] . Looks like they've found quite a few of the regular ones so far. I suppose you'd call this find a "double Solan Lens"?
    • by Suicyco ( 88284 )
      Its only rare in the sense that you have to be in the right place at the right time. There are billions of galaxies scattered all over the universe in all sorts of orientations. If you could choose your vantage point, you could see any number of these. We can't choose our vantage point, so for them to line up just so is pretty rare. Its like seeing a rainbow. You have to catch it at the precise time and angle for you to see anything.
  • Quote: "The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped." Really? How can we "precisely map" something that we have never even shown positively to exist yet? The distribution of gravity could be caused my a number of things other than "dark matter". Gravitational disturbance by itself is not evidence for dark matter, any more than it supports at least several other hypotheses.
    • Re:Propaganda (Score:4, Informative)

      by rush22 ( 772737 ) on Friday January 11, 2008 @02:58AM (#21996068)
      "The distribution of dark matter in the foreground galaxies that is warping space to create the gravitational lens can be precisely mapped." Really? How can we "precisely map" something that we have never even shown positively to exist yet? The distribution of gravity could be caused my a number of things other than "dark matter". Gravitational disturbance by itself is not evidence for dark matter, any more than it supports at least several other hypotheses.

      Yes it is kind of like propaganda to assume dark matter theory is right, but that's the best theory there is. "Dark matter" is just a name for "whatever causes these observations." Whatever it is looks and acts like a gravitational field. Mass produces a gravitational field, so it's assumed to there's some sort of invisible mass, some sort of "dark matter." And they can still "precisely map" the gravitational field, regardless of what is causing it.

      And unless you know something physicists don't know, there's not a "number of things" that could cause a gravitational field like that. Interestingly, there is another theory, ether theory [nationalgeographic.com], but even the physicist who came up with it says: "We're offering an alternative to the dark matter theory--we're not saying it's wrong. If I had to bet today on which of these theories was correct, I might bet on dark matter."
      • Right off the top of my head, there is the MoND hypothesis, which explains these very kinds of observations at least as well as "dark matter", but does not require that we assume that the universe contains at least 3 times as much mass as previously thought (and observed). There ARE others; I am not prepared to expound on them all here. But look up MoND at Wikipedia... as a hypothesis it has advantages over dark matter, and is much simpler... Occam's Razor and all that, you know.

      • Another interesting alternative to the dark matter theory is the TeVeS [physicsworld.com] (Tensor Vector Scalar) theory of gravity. It is powerful enough to explain gravitational lensing, and the Bullet cluster as well.
    • by jbengt ( 874751 )
      The precision they're talking about is probably pretty imprecise by terrestial standards; astronomers are often satisfied if they're within an order of magnitude+/-.

      But the existence of dark matter is not a matter of debate:
      How much of the interstellar dust and debris do you think is visible?
      We've inferred planets that we can't see from the wobble of their stars.
      And, since we can't reconcile the motions of galaxies with the distributions of the visible matter (stars) we try to infer the distribution of unse
      • My point was, as I quite clearly stated, that there are other "theories" (actually hypotheses) that explain these observations at least as well as dark matter, but that do not require that we imagine that most of our universe is not directly observable. REALLY! I know that "dark matter" is the only one that has been spread widely as the "popular theory" (again, it is not a theory at all). But there ARE others. Dark Matter is not the only one out there, nor even the most likely.
  • What I love about this is that it provides an obvious example of a law of physics in action. In high school, my physics teacher told me that gravity distorts space, and my reaction was, OK, sure you can probably come to that conclusion through a long series of complex (or at least clever and not immediately obvious) experiments and lots of math, but I'll have to take your word for it.

    This, however, is a simple, simple thing that causes anyone who looks at the photo to want an explanation. That makes i

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