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Most Distant Galaxy Gives Clues to Early Universe 104

Posted by samzenpus from the in-the-beginning dept.
NinjaT writes "From CNN, 'Scientists said on Wednesday that they have found the most distant galaxy yet, nearly 13 billion light-years away, in a discovery that could help explain how stars were formed at the dawn of time. The galaxy, named IOK-1, is so far away that the light waves that reached Earth depict it as the system of stars existed shortly after the Big Bang created the universe 13.66 billion years ago. That period, known to astronomers as the Dark Ages, saw the formation of the first stars and galaxies from elementary particles. Scientists had been unable to directly observe that time period until now.'"
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Most Distant Galaxy Gives Clues to Early Universe More

Most Distant Galaxy Gives Clues to Early Universe

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  • This is offtopic, so it'll probably be marked down as such.

    I was thinking about matter and how it was created and what we have here on earth.

    The sun is made up of mostly hydrogen, through nuclear fusion, these hydrogen atoms smash into each other and bind into helium. The helium, being heavier than the hydrogen sinks to the center of the sun (or somewhere in there). As the sun uses up its hydrogen fuel, it slowly changes itself into a helium-based star.

    Since we are made of stardust, where do the elements ab

    • Re: (Score:3, Informative)

      by Oizoken ( 562241 )
      I think this will answer your questions:

      http://en.wikipedia.org/wiki/Star#Massive_stars [wikipedia.org]
      • Cool. That does answer my question. How do the elements above 26 get formed?

        • Re:What I find difficult to understand (Score:4, Informative)

          by $RANDOMLUSER ( 804576 ) on Thursday September 14, 2006 @06:24AM (#16102721)
          That's here [wikipedia.org].

          • Re: (Score:1)

            by linzeal ( 197905 )
            and here [ukaff.ac.uk]. This is one of my astrophysics textbooks [amazon.com]. Unfortunately, it is not in print anymore.
            • http://en.wikipedia.org/wiki/Silicon_burning_proc e ss [wikipedia.org]This article answers the particular question of creation of heavy elements.

              Essentially, simplifying somewhat, everything up to Iron gets created inside stars. The heavier elements (than iron) get created in end of life stellar events.

              Simplifications here are that some elements get created inside the star in the last few days to hours of its life rather than over long periods of time and some heavier than iron but unstable elements get created before

              • Re: (Score:2)

                by Alsee ( 515537 )
                BTW, how does the postulated existence of dark matter affect stellar evolution? ...why is this not a problem with the dark matter hypothesis?

                Because in any meaningful sense, quantity of dark matter inside a star is zero.

                Let me clarify what I mean by "zero". By my quick estimate about .000000000000000000005% of the mass inside the sun would be dark matter and the remaining 99.999999999999999999995% would be normal matter.

                Why? To the extent dark matter is gravitationally attracted to a star, it just passes ri

        • Re: (Score:1)

          by Lijemo ( 740145 )
          You're question's already been answered by others, but I just wanted to add a tangental thought.

          In 1056, there was a supernova bright enough and close enough that it was visible in the daytime sky. This was also a time when alchemists were still trying to learn how to turn lead into gold.

          I wonder how many alchemists saw the "new star"-- not realizing that they were witnessing the very transformation they were seeking: since lead CAN be changed into gold-- it just requires (much, much) higher temperatures an
          • The accepted date is probably(July 4), certainly(1054) [wikipedia.org], and the remnant can still be seen: the Crab Nebula [wikipedia.org].

            And no, element 82: lead [wikipedia.org] is actually heavier than element 79: gold [wikipedia.org], so you would have to remove protons and neutrons.

            But thanks for playing, we have a lovely parting gift...

            PS:
            your == belonging to you
            you're == "you are"

            • Re: (Score:1)

              by Lijemo ( 740145 )

              Well, if I measured intelligence in terms of snark, then I'd be forced to bow to your superior intellect.

              However, it would seem that some sources disagree with you (search for "gold" on these pages):

              • http://www.astrosociety.org/education/publicatio ns/tnl/08/08.html
              • http://www.pbs.org/wgbh/nova/origins/univ-nf.htm l
              • http://www.newton.dep.anl.gov/askasci/chem03/che m03691.htm

              I am not an astrophysisist, so it's possible there is more recent information I'm unaware of that makes this assertation out of d

    • Where are these higher-element stars?

      IANAA (I am not an astophysicist) but supernova explosions create most of the heavy elements. There should be a good writeup on wikipedia.

      • Re: (Score:3, Funny)

        by Anonymous Coward
        Please, don't use acronyms ending in AA around here. You're scaring the nerds.

    • Re: (Score:2, Informative)

      by KitsuneSoftware ( 999119 )
      Helium fuses into heavier elements, in a cycle which ultimately leads to carbon for Sun-mass stars, and ultimately to iron for heavier stars. IIRC, elements heavier than iron are only produced in significant quantities by supernova. Such heavy stars are all over the place, and are fairly easy to see because they are so bright; on the other hand, they are also fairly short-lived, lasting only a few million years instead of about ten billion like our sun or the hundred-billion odd years predicted for stars mu
    • In a nutshell, everything up to iron can be done with fusion. Up until iron, you gain more energy out of fusion of cores than it costs to fuse them. Even though it's very, very little when you fuse iron, and only VERY heavy stars get there at all. Fortunately, heavy stars are also those that burn through their fuel the fastest (i.e. they are done after a few million years).

      When iron is done, it's over. The machinery stops. Suddenly. I.e. the pressure from insides stops, the star collapses VERY fast (within
      • So a nova is like a last-gasp fusion step as the star blows itself apart?
        • So a nova is like a last-gasp fusion step as the star blows itself apart?

          Actually I think he meant supernova. Some stars can go nova many times without ending their lives.

    • Re:What I find difficult to understand (Score:5, Informative)

      by FirienFirien ( 857374 ) on Thursday September 14, 2006 @05:14AM (#16102552) Homepage
      Fusion reactions in stars will combine everything up to iron. Hydrogen - being the most abundant - will be the major fusion to form Helium; there's so much of it that that's pretty much all you'll see. However as the amount of He goes up, it'll become combined with H and other He to form Li and Be, and so on - all the way up to iron. Past that the energy of fusion required is simply too high, and with a normal star you'll never see anything with a higher atomic mass. Your iron star going supernova is a little misleading, as the supernova star won't be made of iron - at that mass it'll very likely have a good amount of iron compared to other stars, but in general the greatest part of its mass will still be H and He. Only from that supernova energy, (and the occasional cosmic ray collision, but I think those are negligible in comparison to the amount of matter in a supernova) do you get the energy required to fuse higher elements.

      So - the elements above Helium come from normal fusion in a star; they don't have their own phases, everything just bumps into everything else at once. All your elements above iron have a greater fission energy than fusion energy, and with the amount of trigger radiation inside a star they don't generally last long. When they get ejected from a supernova, there's less to trigger them, so they stay stable for longer; that's why we have everything higher than iron, though even on earth they're in relatively minute quantities.

      One last thing to point out is that your question about carbon seems odd - bear in mind that a carbon atom only has an atomic mass of 12, while iron has an atomic mass of 56. Carbon is relatively abundant compared to iron. To hazard a guess, if you laid the periodic table in a straight line you would probably see an approximately logarithmic amount of each element, up to iron and beyond; it'll be a little complicated since some elements are more likely to decay back to lighter elements faster than others, but that's the gist.

      Disclaimer: this is all out of what I remember from courses; it may not be 100% accurate, though I believe it should clarify things enough.

      • Abundance of elements (Score:5, Informative)

        by Roy Ward ( 14216 ) <royward770&actrix,co,nz> on Thursday September 14, 2006 @05:39AM (#16102607)
        > To hazard a guess, if you laid the periodic table in a straight line you would probably see an approximately logarithmic amount of each element, up to iron and beyond; it'll be a little complicated since some elements are more likely to decay back to lighter elements faster than others, but that's the gist.

        Not quite right:

        http://www.seafriends.org.nz/oceano/abund.htm [seafriends.org.nz]

        Some elements (Oxygen, Carbon, Neon) seem to form more easily than Lithium, Beryllium etc.
        • I was surprised by this so have looked into it; a Wikipedia page seems to explain why the lithium goes, and implies that most of the Be formed is 8Be which degenerates back to two 4He. Must have been asleep in that lecture or something...
    • Iron is the last step in fusion, and stars that go supernova do build up 1.2 solar masses of the stuff. Except when they implode, everything is turned into neutrons. So, fusion as a positive energy reaction doesn't happen above iron, and supernova's only contribution would be what happens to be outside of its core.
    • Fundamentally the universe isn't old enough yet to have any (or many...I guess somewhere out there might be one or two) higher-element stars. From the stars' point of view most heavier elements are "trash" in one form or another...if they're made largely by previous stars fusion process and/or when they supernova you can't have any significant amount of heavier elements until a first generation star burns through its fuel, blows up, forms a second-gen star, IT blows up, etc.

      I think I read that right now th
    • BadAnalogyGuy, I'm highly dissapointed that your post doesn't contain a bad analogy. Damn, not even any analogy! I hereby express my desire to see a bad analogy in each of your future posts (and I know you've done it in the past :P).
      • Why're you surprised? BadAnalogyGuy's posts are like getting a used car, they may not live up to expectations. It'd be like if you go to a used car lot called "Honest Bob's", and then are surprised that you get a slimy deal.
    • I'm not an astronomer either (I do read a good bit about it though), but yes, the heavy elements that make us and all the "heavy" planets up were formed in supernova explosions.

      It's also just a guess, but overly massive stars and accompanying supernovas would have have been much more common in the early universe. Combine that with a greatly reduced lifespan for these massive stars (last I heard the really big ones might have a life cycle measure by a couple dozen millions of years, rather than billions), a

  • The galaxy, named IOK-1 (Score:2, Funny)

    by Anonymous Coward
    Well I think that name is A-OK.

  • I know cosmology is an inexact science but (Score:3, Funny)

    by Silver Sloth ( 770927 ) on Thursday September 14, 2006 @04:55AM (#16102497)
    From TFA
    The scientists found another object similar to IOK-1, but could not say if it was a distant galaxy or something else such as a black hole.
    • Galaxy - lots of stars spread over a vast area - low average density
    • Black hole - one star compressed into a relatively small area - high average density
    Easily confused then.

    • Re:I know cosmology is an inexact science but (Score:5, Informative)

      by HuguesT ( 84078 ) on Thursday September 14, 2006 @05:08AM (#16102534)
      From very far away they are not so easy to tell apart. Essentially these are two objects that emit extremely red-shifted light.
      • >Essentially these are two objects that emit extremely red-shifted light.
        So it's very, very old and emits red light? Sounds like they've just spotted the first ever brothel.

        • Re: (Score:2)

          by HuguesT ( 84078 )
          Hello, the straight-type, no fun answer is that red-shifted doesn't mean red. Extremely red-shifted gamma rays might be X-rays for instance.
    • Easily confused then.

      TFA doesn't say but I suspect they are not actually looking at pictures of the object. More likely a spectrum. Perhaps the acretion disk of a black hole has a similar spectrum to a young galaxy when using these instruments.

    • Well, considering it's really far away (I mean, 13 bil LJ ain't just 'round the corner), I can well see that it's hard to discriminate between a galaxy and a black hole. From that distance, both are just huge things in space with lots of (singular or combined) gravity.
    • "The thing about black-holes is, they're black. And thing about space - the colour of space; your basic space colour - is it's black.

      "So 'ow you s'posed to see 'em?"

      </geek>
      • Ahhh Red Dwarf. Up until season 7 was perhaps the greatest Sci-fi comedy ever. (Though futurama might have overtaken it now). If you have not yet seen it then do yourself a favour and watch it [thepiratebay.org]. (but bare in mind it dates back to 1988).

        • Re: (Score:2)

          by Aladrin ( 926209 )
          It's 'bear in mind' but other than that, spot on. Absolutely hilarious. Don't get turned off by the first ep, though. It's a tad slow at the start.

  • Not quite science reporting (Score:4, Insightful)

    by svunt ( 916464 ) on Thursday September 14, 2006 @05:14AM (#16102554) Homepage Journal
    Whoever wrote up the Reuters summary that CNN are running must've been filling in for the science reporter.


    I was well impressed by this guy confirming the Big Bang, and its precise timing. Correct me if I'm wrong, but I thought that the exact origin of the universe and its date were still debated issues. We've changed the age of the universe enough times that you'd want to be wary about putting two decimal places in your statement.


    Disclaimer: I'm not a creationist or one of the "evolution's a theory, not a fact" crowd, I just like my science to come appropriately qualified.

    • I thought this was a bit bold:

      Either way, it shows that the universe changed substantially in the 60 million years that separate IOK-1 and the next oldest galaxies to be observed on Earth, the astronomers said.

      Considering that we are talking about the first billion years after the big bang.

      • Re: (Score:3, Insightful)

        by svunt ( 916464 )
        Yep, all in all, whoever wrote this really lacks any understanding of the scientific process. I'm sure the astronomers who made the find would've been a little bit more careful about their claims than the article suggests.
    • Not so much anymore. Since WMAP [wikipedia.org] it has generally been accepted that 13.7 billion years is the best bet, with a few theories here and there that claim to give a more accurate date.
  • in a galaxy, far, far away...

    I finally made my first post, it's just now arriving from IOK-1.

    --Not enough Bothans died to bring you this message.

  • What doesn't make sense to me is how galaxies nearly 13 Billion light years away are determined to be nearly as old as the Universe. My intuition tells me that light that old would have already passed us by soon after the big bang happened?
    • The Universe is about 78 billion lightyears accross. Although it doesn't seem to make sense, I think it is to do with relativity.
      The oldest radiation that can reach us is from about 400 000 years after the big bang when atoms formed, which let light pass through and the universe became transparent.

    • 13.7 billion years is the best guess at the age of the universe now. that light arriving at us now is depicting the galaxies as they were 13 billion years ago, very close to the big bang.

      i believe that around 380,000 years ago is the earliest we'll be able to observe, because before then, the universe was so hot that it was opaque, and no light escaped without being abosorbed by other particles.

      • actually, i think because of the expansion of the universe, it was probably less than 13 billion years ago, but i'm not sure how much less.

    • Re: (Score:2)

      by x2A ( 858210 )
      "My intuition..."

      oo you don't wanna be using a thing like that here! What you have to remember is that this galaxy we're viewing is in the same location that the big bang occured... and so are we. :-/

  • The original article is, of course, here [naoj.org].
    I'd like to see science news announced here by quoting the original source rather than a news company.

  • Moo (Score:1)

    by Chacham ( 981 )
    The galaxy, named IOK-1, is so far away that the light waves that reached Earth depict it as the system of stars existed shortly after the Big Bang created the universe 13.66 billion years ago.

    Amazing how it is just taken as a fact.
  • The article states the galaxy is 13 billion light years away. At first I read this as "the light took 13 billion years to reach us," but that doesn't make sense if you think about it. To get 13 billion light years away in a galaxy which is a mere 13.6 billion years old, each galaxy would need to be moving at nearly 0.48c. Assuming that the galaxies are moving in opposite directions at the same speed, this means that the light has been catching up to us at a rate of 0.52c since the time it left the other gal
    • Sorry, but no. Remember that the fundamental given that underlies all relativity is that light moves at the same speed regardless of the motion of the observer. In other words, regardless of our relative movement, the speed of light must be c, not 0.52c. Therefore, this galaxy would have had to have been 13 billion light years away from us at the time the light left it and began travelling towards us. Of course, that's assuming relativity is correct, which is much less certain than many people believe.
      • Therefore, this galaxy would have had to have been 13 billion light years away from us at the time the light left it and began travelling towards us.

        This isn't right. The "13 billion ly" is an unfortunately inaccurate, and probably meaningless number. It typically comes from plugging the value of the *redshift* of the galaxy (what is actually observed) into a particular cosmological model or, more commonly and naively, into simple Doppler redshift formulae. The distance of the galaxy at the time of e

        • The "13 billion ly" is an unfortunately inaccurate, and probably meaningless number.

          I agree, but I didn't feel like taking on this assumption. I was simply stating that if something were indeed seen from 13 billion ly away, it would mean they were 13 billion ly away 13 billion years ago, when the light began travelling, as opposed to being 13 billion ly away right now. On the other hand, if the other galaxy is calculated to be 13 billion ly away now, it was much closer when the light we are now seeing

          • Re: (Score:3, Informative)

            by wanerious ( 712877 )
            I agree, but I didn't feel like taking on this assumption. I was simply stating that if something were indeed seen from 13 billion ly away, it would mean they were 13 billion ly away 13 billion years ago, when the light began travelling, as opposed to being 13 billion ly away right now. On the other hand, if the other galaxy is calculated to be 13 billion ly away now, it was much closer when the light we are now seeing had left it. I addressed the former possibility because it related to the parent post.
            • The statements (a) "The galaxy was 13 billion light years away when the light was emitted" and (b) "The galaxy is now 13 billion light years away" are both not only wrong, but meaningless.

              If you're going to trivialize all values of distance to the point that they are meaningless, then you're a fool. It's certainly possible to say that variations in theoretical values (or entire cosmological models) could cause these values to be different, but the gist remains the same: the light left the other galaxy
              • I'm afraid I've been unable to find a visual example of the thought experiment I mentioned. I know I've seen it on the web before, but there are so many search results that I couldn't find that specific one. There is a similar one where "Bob" flies a ship to another planet and back and "Ann" stays on Earth and watches, but it doesn't show the reasoning behind relativity - ie. the fact that light has the same constant speed regardless of inertial frame. It just shows the application of time dilation. How
              • If you're going to trivialize all values of distance to the point that they are meaningless, then you're a fool.

                Ok, I'll try again --- we can basically agree on local values of distance because, for a receding car on the freeway, the light travel time between the car and us is much shorter than the increase in the distance of the car during this light travel time. On larger scales, where the increase in separation due to the expansion of the universe is still significantly less than light speed, it's no

                • Once again, you completely misunderstand. I, along with the author of the article, am using a simpler cosmological model so that we can give a number that means something to others, instead of stupidly reducing everything to meaningless jargon. Actually, I was simply trying to correct the previous poster's misconception that light has to "catch up" to us at a speed of "c minus our speed." I never denied that cosmological expansion would effect the real value of the distance, but I chose to use a model th
                  • You've completely missed the point of the thought experiment. It assumes Newtonian physics, along with the premise that light travels at the same speed regardless of inertial frames. Thus it demonstrates the need for length and time dilation.

                    No, I get the point of the thought experiment, it's just a really poor and misleading demonstration that something like special relativity must be true. Glancing at any elementary-level text will reveal many better thought experiments that utilize the correct conc

                    • I most certainly did not insinuate that there was a conspiracy. What you inferred is your fault. However, if there were a need for such a conspiracy, you would clearly be a part of it. I'll tell you what, if you think that acceleration can account for the differences in the thought experiments given, why don't you show me the formulae in which said acceleration is accounted for?
                    • Let me clarify - give the formulae in which the force behind the acceleration is taken into account. Acceleration, just like velocity, is symmetrical. From the perspective of the ship, the planet accelerates away from it.
                    • Let me clarify - give the formulae in which the force behind the acceleration is taken into account. Acceleration, just like velocity, is symmetrical. From the perspective of the ship, the planet accelerates away from it.

                      No. This is what I'm saying --- it's *not* symmetrical. Only the ship is in an accelerating, non-inertial frame. Giving an observer in each frame the little box with a ball in the center, only the one on board the ship will move in response to its acceleration. Both observers will ag

                    • I agree. Only one observer will see the ball move. BUT RELATIVITY DOES NOT ACCOUNT FOR THIS IN ANY EQUATION! That is why it is fully possible to model the planet moving and the ship sitting still. Also, this does not address the cases in which both observers are moving equally.
                    • BUT RELATIVITY DOES NOT ACCOUNT FOR THIS IN ANY EQUATION!

                      Of course not. It doesn't apply in that case. The Second Law of Thermodynamics does not account for the motion of an electron in a magnetic field, but we shouldn't infer that there's anything wrong with the thermodynamics because of this. There are regimes where we should use results from SR, and regimes where we shouldn't.

                      That is why it is fully possible to model the planet moving and the ship sitting still

                      Nope. It's completely different

                    • I don't understand this.

                      Obviously. You clearly haven't been paying any attention. I am referring to two ships which start at rest and move in mirroring ways. Each accelerates the same as the other, but in opposite directions. I've already given you two examples; I'm not going to explain again.

                      I'm starting to think you're nothing but a troll, or perhaps just an idiot who made a stupid comment and refuses to back down. Either way, this has clearly gotten pointless. If you really don't understand,
                    • You continue to trot out the same inaccurate language and examples, and I've refuted every point. And, for what is now the last time, I'll reiterate that by invoking the word "accelerates", you've lost all rights to compare results derived using SR. Along the way somewhere, you have been hoodwinked by people claiming much more knowledge than they truly possess. Please stop listening and linking to crackpots, and open a good text on the subject and start studying for yourself.

                      Ok, I've had it. You've be

                    • I never said specific relativity. I include general in this, though it's irrelevant in some cases. The thought experiment postulated on the page I referenced is entirely valid without any need to factor in acceleration. And before you stupidly point out that the ships must undergo acceleration to return and compare notes, I'll point out that all special relativity then becomes vacuous and moot, because no results could ever be compared without such acceleration. It is not unreasonable to expect general

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