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Space Science

Astronomers Find Most Distant Protocluster of Galaxies 129

The Bad Astronomer writes "Using the monster 8.2-meter Subaru telescope, astronomers have identified the most distant cluster of galaxies ever found: a collection of galaxies at a staggering distance of 12.7 billion light years. This is the most distant cluster ever seen that has been confirmed spectroscopically (PDF). Technically, it's a protocluster, since it's so young — seen only a billion years after the Big Bang itself — the cluster must still be in the process of formation."
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Astronomers Find Most Distant Protocluster of Galaxies

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  • by CosaNostra Pizza Inc ( 1299163 ) on Monday May 07, 2012 @01:36PM (#39917993)
    Includes all-wheel drive and a boxer-engine.
  • incredible (Score:4, Insightful)

    by Anonymous Coward on Monday May 07, 2012 @01:40PM (#39918031)

    It is incredible what we can accomplish as humans, imagine if we did not waste trillions on useless battles for the hear and minds of primitive retarded people with stone age believes.

    • by Anonymous Coward on Monday May 07, 2012 @01:55PM (#39918213)

      Yes, we could spend some of that to educate folks like yourself on how to write properly!

    • It is incredible what we can accomplish as humans, imagine if we did not waste trillions on useless battles for the hear and minds of primitive retarded people with stone age believes.

      Stone age believes like self determination and freedom from foregin invaders looking to implement cultural and economic imperialism? That sort of believe?

  • by Anonymous Coward
    So.... It's almost as old as your mom?
  • 12.7 billion years ago it might have been 12.7 billion light years away, but where is it now?

    • Right behind you!
    • Come back in 12.7 billion years and I'll let you know.

    • by arth1 ( 260657 ) on Monday May 07, 2012 @01:56PM (#39918227) Homepage Journal

      12.7 billion years ago it might have been 12.7 billion light years away, but where is it now?

      Exactly where we see it. The 12.7 billion years haven't passed, because there is no common point of reference between us and them for that time to have passed in.
      "Now" and "then" makes no sense except for local distances, without introducing FTL, time travel and violating causality. We can only measure round trip times, not one way time.
      The photons haven't experienced 12.7 billion years of travel - they just left.
      If this makes your head hurt, good.

      • The photons haven't experienced 12.7 billion years of travel - they just left.
        If this makes your head hurt, good.

        Wait, what? If the photons travelled at the speed of light, they've been doing that for 12.7 billion years.

        Assuming photons can count and measure time, would they really "see" this as instantaneous? Or would they have had time to catch up on their reading?

        Relativity and light speed are so damned confusing some times.

        • by MightyMartian ( 840721 ) on Monday May 07, 2012 @02:15PM (#39918405) Journal

          Short answer: yes. For anything traveling at luminal speeds, time is not perceived. If you were a photon, it might take you 12.7 billion years to get here, but for you it is an instant.

          • Actually if I understand special relativity correctly, time dilation only actually takes effect when something moving at relativistic speeds slows back down to the same speed as its reference. Since photons never slow, they don't actually experience time dilation. Not saying I actually know what I'm talking about...
        • by Anonymous Coward

          I think he's wrong.

          From the photon's point of reference, it traveled instantaneously. From our point of reference, it took 12.7 billion years for the photons to reach us.

          Therefore, what we're seeing is how it looked 12.7 billion years ago.

          • by arth1 ( 260657 )

            From the photon's point of reference, it traveled instantaneously. From our point of reference, it took 12.7 billion years for the photons to reach us.

            Therefore, what we're seeing is how it looked 12.7 billion years ago.

            Your error is to apply the word "ago". That implies that time passes here and there in the same frame of reference - a universal clock, if you like. That doesn't exist - time is only a local phenomenon.

            From our point of view, it did not take 12.7 billion years for the photons to get here, because from our point of view, 12.7 billion years ago, that part of the universe didn't exist. There is no "then" common to us and them; only a blossom slowly opening and revealing parts of the universe to us that's ne

            • by gstoddart ( 321705 ) on Monday May 07, 2012 @02:56PM (#39918961) Homepage

              because from our point of view, 12.7 billion years ago, that part of the universe didn't exist

              Oh come on, do you guys just make this stuff up as you go? ;-)

              No, seriously, I actually understood that we were seeing what was there 12.7 billion years ago -- WTF does it mean then? I thought this was what existed 12.7 billion years ago from our point of view.

              only a blossom slowly opening and revealing parts of the universe to us that's new to us

              That sounds dirty, and I'm not sure if it actually sheds any, er, light on this.

              I think this actually confirms what I knew in university -- astrophysicists must spend much of their time drunk in order to be able to reconcile this stuff with everything else.

              • by arth1 ( 260657 )

                No, seriously, I actually understood that we were seeing what was there 12.7 billion years ago

                There you use that word again. "Ago" doesn't make sense at relativistic speeds and vast distances.

                It's 12.7 billion light-years distant. Light-year is a distance, not an age.
                If you travelled that distance and back at the speed of light, we would have to wait 25.4 billion years for your return. But your travel would not take that time. A person at your turning point, 12.7 billion light years distant, would not have seen you 12.7 billion years ago when you come back to us. He would just have seen you le

                • by Bengie ( 1121981 )

                  Light-year is a distance, not an age

                  But when light goes the speed of light, the distance also becomes an age.

                  As much as I appreciate your first few corrections, your on-going determination to be a grammar-nazi is not appreciated.

                  • by arth1 ( 260657 )

                    But when light goes the speed of light, the distance also becomes an age.

                    No, that does not follow. I am sorry, but it really doesn't, because time is not a constant.

                    As much as I appreciate your first few corrections, your on-going determination to be a grammar-nazi is not appreciated.

                    This isn't about grammar, but about the error of applying Newtonian physics to relativistic speeds. In Newtonian physics, it is obvious that going 100 km at 100 km/h would take one hour. But in relativistic physics, it doesn't - going 1 lyr at 1 lyr/y doesn't take 1 year.

                    If you in year X send out a probe at 1 lyr/y (c) for a distance of 1 lyr, and have it return immediately, it would take 2 years (not factoring in

              • by Clith ( 5063 )
                12.7 billion years ago our point of view didn't exist either. The universe was only around 1 billion light-years across. You might think that would mean all light would arrive at a destination in 1 billion years or less. You would be wrong. :-)
              • by Lithdren ( 605362 ) on Monday May 07, 2012 @03:12PM (#39919183)
                All it really proves is that humans cannot comprehend distance as vast as this.

                My understanding, and im sure its flawed, is that something like a Photon doesn't experience time. To it, it pops into and out of existance, one end at the surface of a star in a galaxy cluster 12.7 billion light years away, the other end at the Subaru telescope in this case. Just as suddenly as this happends, its gone again.

                This is because its traveling at the speed of light. Time and space are linked. Beyond this my understanding breaks down, but I suspect it has something to do with moving through space at that speed, and our misunderstanding of what time really is. We experience time where there is a 'universal' time in our refrence, because really anything we need to reference is already here, moving with us at the same speed around the sun. There is no 12.7 billion years ago to this galaxy, per our reference, because nothing that is happening 'now' as you and I understand it can possibly affect us here, without violating the speed of light. We're not looking at a galaxy we're literally looking back in time at a galaxy. If this galaxy exploded ripping a hole in the fabric of space-time and ended the entire universe right now, we'd not be aware of it for another 12.7 billion years. Per our reference, nothing has happened, or will happen, for that span of time. So in effect, for us, what we're seeing is what IS happening.

                Now please correct my misunderstanding, those of you lurking out there who do know better, because i'd love to understand all this!
        • by arth1 ( 260657 )

          Wait, what? If the photons travelled at the speed of light, they've been doing that for 12.7 billion years.

          Only from an outside point of view, of which there are none. We only see the end of their travel.
          From their point of view (if you could piggy-back on them in a space ship going the same speed), only an instant has passed, while the rest of the tiny universe aged.

          Relativity and light speed are so damned confusing some times.

          It sure is. One of the most difficult thing to grasp is that time is a purely local phenomenon, and that you can't apply "now" to anywhere else. Even such a thing as "the age of the universe" is our age of the universe. What the age of the unive

          • It sure is. One of the most difficult thing to grasp is that time is a purely local phenomenon, and that you can't apply "now" to anywhere else.

            May I be excused? My brain is full [flickr.com].

            I honestly don't know how physicists keep it straight -- verb tenses must be a bitch. When the photon will have arrived yesterday after it's long journey of instantaneous, we will have known tomorrow what something looked like billions of years ago but never not almost today. Next year, we might know what happened before that.

            So

            • by Anonymous Coward

              Actual physicists would probably tell you that if we could get a decent handle on the cluster's state and location 12.7 billion years ago from these visual observations, we could make a reasonable projection, taking the two reference frames into account, as to the cluster's current state and location. It is still out there, somewhere, right now, in some state.

              All the pseudo-mysticism in this discussion is a load of nonsense by geeks trying to sound intelligent.

            • by tibit ( 1762298 )

              Terry Pratchett took this to the logical conclusion in his vision of the Discworld. Listen in to some conversations going on at the Unseen University, and generally with wizards in Discworld, and you'll hear stuff that makes just about as much "sense". Nature is a bitch :)

      • The photons haven't experienced 12.7 billion years of travel - they just left

        Implying the photons were teleported straight to the lens of the Subaru Telescope. Unless you can show that those photons somehow violated or evaded the constant "c", you can damn well bet your ass those photons have experienced a duration of travel at the speed of light from their point of radiation to our planet's present position.

        • The speed of light is infinite, because due to relativistic effects, time has stopped. Only an outside observer sees something moving at the "speed of light"; to the photon itself, no time passes.

          • by Anonymous Coward
            OK, I get that. But we aren't talking about photons here really. We are talking about something on the other end - where the photons come from. That isn't a photon and it isn't moving at the speed of light. While true that we can only get information about that place via photons, it is not true that we are observing that far off location as it is today. Sure the photons have experienced relativity, but the location hasn't. For example:

            Let's say I am 1,000 light years away and I flip you off.
            By the time you
          • Only an outside observer sees something moving at the "speed of light"; to the photon itself, no time passes.

            Not really. This was a research project, which means the very last part of the photon's trip was through part of academia. Which means it felt like exactly like 12.7 billion years.

        • by arth1 ( 260657 )

          Implying the photons were teleported straight to the lens of the Subaru Telescope.

          No, implying that distance and time aren't constants, but vary depending on your frame of reference.

          • So you are denying that the astronomers who captured these photons with their telescope have a frame of reference?
            Saying the duration of travel a photon experiences is imaterial because the photon has no awareness is saying that there is no sound if a tree falls in the woods and no one is there to hear it. We all know that it *must* have interacted with the atmosphere and made a sound -- regardless of anyone being there to hear it. As such, the light traveled at the speed it always travels, we happen to obs

            • by arth1 ( 260657 )

              So you are denying that the astronomers who captured these photons with their telescope have a frame of reference?

              No common frame of reference? Yes, most certainly there isn't one, and the astronomers would agree. They only capture the photons as they arrive here, and can tell by the red-shift how far away the proto-galaxy is. But they can't tell anything about time, because the speed of time itself can't exceed the speed of light - there's no big Pratchettian clock that ticks time for everywhere in the universe.

              When something happens elsewhere, it hasn't happened at all until the light cone hits us. Or, to put it

    • The funny thing about relativity is that is that in our frame of reference, this is happening NOW, not 12.7 billion years ago.
      • That's what I've never understood. For it to be happening right now, to me, it stands to reason that if we look far enough away we could see the light from the big bang. Which means that everything that has ever happened is always happening everywhere. Which means that we always have existed in the state that we exist in today and will always exist in the state that we existed in billions of years ago.

        Oh no, I've gone cross-eyed.

        • by MightyMartian ( 840721 ) on Monday May 07, 2012 @02:18PM (#39918451) Journal

          You couldn't see light from the Big Bang itself because it took until nearly 400,000 years after the Big Bang for the Universe to cool sufficiently for photons to find a clear path through the charged ions. It's this first wave of freed photons that form the Cosmic Microwave Background Radiation.

          • That didn't help my brain.
            • I'm not sure what's confusing you. Look, how time is perceived (excluding any particular psychological phenomena) is a function of speed of the object in question; it's all relative to the frame of reference of the observer. The faster you go, the slower external time passes (not your own time, mind you, just the time of anything not moving as fast as you are). The closer to the speed of light you go, the slower time passes, until finally you have a photon which always moves at the speed of light, time does

              • Did time existed before universe was created? Are first ever protons created the holy grail of time/space? Where is the initial first light from the Big Bang? - according to this theory it didn't arrive yet or suntin. I have wasps in my brain... (faints)
                • Other than some string theorists, I think most physicists are of the opinion that time-space did not exist prior to the Big Bang.

                  • Other than some string theorists, I think most physicists are of the opinion that time-space did not exist prior to the Big Bang.

                    According to string theorists, prior to the Big Bang, the Silly String was in the Big Can. Then it was squirted out forming the universe. One variant of this holds that it was Pasta not Silly String.

                  • by Bengie ( 1121981 )
                    I always wondered how that worked. If time didn't exist, how did the big-bang happen in the first place? An event cannot happen outside of time, yet an event was required to create time. --I am not a scientist.
        • it stands to reason that if we look far enough away we could see the light from the big bang

          This [wikipedia.org] is pretty much what you are looking for.

      • by Bengie ( 1121981 )
        That implies that for a given event, it must happen once for every possible frame of reference. Being an infinite frame of references, a given event must happen an infinite amount of times, meaning there is an infinite amount of energy as an event requires energy. It is not "happening now", we are just looking at delayed measurements of an event that happened a long time ago.
        • by Quirkz ( 1206400 )
          A different frame of reference doesn't make the event happen a second time, just that the timing of the event isn't consistent between one frame of reference and the next. Seeing something sooner or later doesn't change the energy of the event.
    • Probably long dead. Since these were the "first" stars/galaxies from the beginning of the universe, they've long since exploded and are now part of the "near by" most recent stars and galaxies we're most familiar with. They are part of us.

    • by NEDHead ( 1651195 ) on Monday May 07, 2012 @02:05PM (#39918321)

      Wrong on several counts. What the 12.7 refers to is when the light left the cluster in question (in billions of years). At the time the light left the cluster it was actually much closer to us than 12.7 light years. The observable universe is actually larger in light years than the time since the Big Bang, due to the expansion of space. This expansion also stretched the travel time for the cluster's light to reach us. Now the cluster (to the extent 'Now' has any meaning) may be 25+ light years away (I apologize for the imprecision, as I don't have the exact figures at hand).

    • There is no absolute "now" in the universe since we have the concept of relative simultaneity. The photons reaching us from there have "just left" according to them even though they may seem to have traveled a huge distance according to a third party observer. Since time dilates and space shrinks as you approach the speed of light, every photon reaches its destination "instantly"

      So while we can talk about "now" and "then", it's meaningless on an absolute scale. For this reason, when light from someplac
    • Dont know accurately, though there is a way to measure that. but based on Dark energy theory,It would be around 40 billion light years away right now.
  • the cluster must still be in the process of formation.

    Well, it's still in the process of formation where we can visibly see it. Given that it's 12.7 billion light years away, I'd like to believe that the galaxies are properly formed at this point. Though, given that not one person knows exactly how long it takes to form a proper galaxy, who's to say that it isn't finished. It's all best guess I suppose. Really cool science though, knowing that light from 12.7 billion years ago is illuminating our planet, however faint it may be.

    • by Java Pimp ( 98454 ) on Monday May 07, 2012 @02:04PM (#39918317) Homepage

      Perhaps the universe is in fact curved and 12.7 billion years "across" and we are looking at the formation of the milky way and other local galaxies...

      • by Surt ( 22457 )

        No, we have enough evidence to know that isn't true. There are plenty of galaxies visible with the wrong masses to tell us that if the universe is curved the curvature doesn't loop within the size of the visible universe.

    • There is no "at this point" since absolute simultaneity doesn't exist in the universe. Consider this: The photons reaching us from that place have only "just left" according to them! So for us to say "right now" means very different things depending on your frame of reference.
  • by Anonymous Coward

    Technically, it's a protocluster, since it's so young — seen only a billion years after the Big Bang itself — the cluster must still be in the process of formation.

    Scientists may only be detecting its protocluster stage because the light from its current stage hasn't made it here yet, but I'm willing to bet good money that it's neither young, nor a protocluster, nor still in the process of formation.

  • by Anonymous Coward
    They might be able to find the Destiny.
  • by Zharr ( 879496 ) on Monday May 07, 2012 @02:21PM (#39918485)
    To paraphrase: Astronomer: What am I looking at? When does this happen in the Big Bang? Telescope Operator: Now. You're looking at now, sir. Everything that happens now, is happening now. Astronomer: What happened to then? Telescope Operator: We passed then. Astronomer: When? Telescope Operator: Just now. We're at now now. Astronomer: Go back to then. Telescope Operator: When? Astronomer: Now. Telescope Operator: Now? Astronomer: Now. Telescope Operator: I can't. Astronomer: Why? Telescope Operator: We missed it. Astronomer: When? Telescope Operator: Just now. Astronomer: When will then be now? Telescope Operator: Soon.
  • by JSBiff ( 87824 ) on Monday May 07, 2012 @02:29PM (#39918585) Journal

    Whenever one of these astronomy articles comes up about seeing a galaxy or cluster "near the big bang", there's one fundamental question which has always bothered me. . .

    We are told that the universe is expanding, and has been expanding for about 14 Billion years. This means that everything was much closer together back 13 Billion years ago (when the summary says we are seeing the light from). Also, light travels much faster than the universe expands. So. . . why didn't the light pass us billions of years ago?

    I realize that light takes time to travel, and that's the idea behind the idea that we can "look back in time" when we look at very distant astronomical objects. . . but. . . again, why didn't the light PASS US billions of years ago, since light expands outward faster than the universe expands outward? Wouldn't the universe need to have been expanding at almost the speed of light, for us to just now receive light from 13 Bn years ago? Well, that is, that the expansion would have had to happen at about 13/14 C?

    • The universe is expanding at the exact speed of light at it's "edge" (at least the edge we can just barely not see). It's expansion appears to slow on objects closer to us. So this light has been trying to travel across space as it was expanding. The distances it had to travel kept expanding and it eventually reached us after traveling for 12.7B light years (from our perspective).
    • Re: (Score:2, Informative)

      by Anonymous Coward

      A quick answer is to say that the universe assuredly is expanding faster than the speed of light. Or rather, it's expanding at some rate, and two sufficiently distant points will be receding from one another at the speed of light, or even greater than the speed of light. (You've no doubt heard that "nothing can travel faster than c" but in fact it's really that "energy (hence information) cannot propagate faster than c"... according to relativity spacetime itself can expand at any speed.)

      A more detailed exp

    • The premise of your argument is that the expansion of space can't cause the distance between two objects to increase at a rate greater than the speed of light. I don't know where you got that from, see http://en.wikipedia.org/wiki/Expansion_of_the_universe [wikipedia.org].

    • Initially, the expansion of the universe was a lot faster than the speed of light: the universe got really large very shortly after the bang.

    • That's been one of the things I've wondered about. How close were "we" to that galaxy when the light was emitted, how far have we traveled in the time since the light was emitted and "chasing us". How far back can we possibly see before any light emitted has overtaken us?
  • "..... distance of 12.7 billion light years. "
    If an object is 12.7 billion light years from us, the time that light takes to travel to us takes.... 12.7 billion years.

    " ...the cluster must still be in the process of formation."
    Nope. It _was_ in the process of formation about 12.7 billion years ago. Now that said cluster is 12.7 billion years older, and it is either very old or blown away to bits and pieces some time ago.

    The distance works like a time machine, and for example we see and experience our Sun ab

    • by slew ( 2918 )

      Although I'm sure that many introductory physics students might love it if somehow time was somehow independent of distance so you could just easily convert light-years to distance, but it is not. As explained by numerous posters on this thread, there are a couple of big issues with this simplification.

      First, the distance to the clusters in question is infered from its red-shift (which it gets from the actual fabric of space itself expanding). The actual paper implies the cluster is approximatly z=6 (wher

      • by Bengie ( 1121981 )
        It's only a paradox because it ignores other's frame of reference.
        "If I completely ignore these variables over here, this makes no sense! It's a paradox!" - Surprise? It is a fun thought exercise.

        "from the photon's point of view"
        From birth to death, the photon has always been traveling at the speed of light. If no time has ever elapsed for it, how could it have a "point of view"?
        Let me phrase that a bit differently. If something "existed" for a time of exactly 0, then it never existed at all. From its
  • "Astronomers Find Most Distant Protocluster of Galaxies" - seems to imply a finite universe. That probably makes half the physicists in the world happy...

    • Yes, well, whether or not the universe is finite, the headline certainly was, and some things didn't fit.

      The summary clarified: "This is the most distant cluster ever seen that has been confirmed spectroscopically."

    • The article baldly assumes as much. It would be nice if we could get back to the days in which the data was primary and cosmological theories were secondary.

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