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Furthest Gamma-Ray Burst Ever Observed 273

jd writes "The SWIFT team have announced the furthest-ever observed super-massive gamma-ray burst (from 13 billion light years away). The burst was observed on the 6th of September and lasted for 3 minutes - long enough for a number of other telescopes to home in on the gigantic explosion. The distance is only barely within the reaches of the observable universe. The idea of the SWIFT telescope and follow-up observations is that they will discover both the cause of the bursts and the consequences to the star."
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Furthest Gamma-Ray Burst Ever Observed

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  • by mr100percent ( 57156 ) * on Wednesday September 14, 2005 @12:33AM (#13554158) Homepage Journal
    I feel a great disturbance in the Force (which we all know travels at the speed of light). As if millions of voices suddenly cried out in terror, and were suddenly silenced.
  • by slothman32 ( 629113 ) <pjohnjackson@gmail. c o m> on Wednesday September 14, 2005 @12:35AM (#13554172) Homepage Journal
    When supernovae occur you can see them. Are they the brightest visible object? What would this look like if it were light instead of gamma? Or even alpha or beta?
    • When supernovae occur you can see them. Are they the brightest visible object?

      Galaxies are the brightest visable objects. Well, actually quasars are, but are thought to be galaxies or at least closely related to them. But the total energy put out by gamma bursts is far larger than the energy put out by supernova. It is just that they do it over a wider area of the spectrum such that their visible light component is roughly comparable to supernova but beat them by far in higher-energy radiation.
    • by mbrother ( 739193 ) * <mbrother@uwyoWELTY.edu minus author> on Wednesday September 14, 2005 @12:49AM (#13554252) Homepage
      Well, the leading idea about (this type of) gamma ray burst says that they're associated with supernovas. So, they look like supernovas.

      Quasars are the most luminous long-lived light sources. Gamma ray bursts can release more energy for short periods of time, but there are arguments about to what extent the energy is beamed in a preferred direction (complicating efforts to calculate total energy released).

      I'm not sure what you mean by "alpha and beta?" Are you talking about alpha and beta radiation? Apples and oranges, although all are called "radiation". Gamma rays are a form of light (very high energy photons), while alpha and beta radiation isn't electromagnetic radiation at all, but rather particles (He nuclei and electrons).
    • i forgot, in OUR night sky, within the visable light spectrum, the moon is surely the brightest object, followed by venus, some other planets, and then i believe sirius. I supposed a realtively close and bright supernova could outshine all the other stars, and maybe even all the planets, but it would have a tough time competing with luna.
      • by mbrother ( 739193 ) * <mbrother@uwyoWELTY.edu minus author> on Wednesday September 14, 2005 @01:09AM (#13554356) Homepage
        For a homework problem, I have my astronomy students calculate how bright the Galactic core would be if it were a quasar and there wasn't any obscuring dust in the plane of the galaxy. It turns out to be about the brightness of the full moon, but since it would be smaller, it would be more striking. That's at a distance of 8 kpc or so.
  • by Propagandhi ( 570791 ) on Wednesday September 14, 2005 @12:37AM (#13554183) Journal
    Imagine there are a few people rather lost at the headline (we're not all astronomers/cosmologists/whatever :) ). Anyway, NOVA ran an excellent show on this a couple years ago, and as usual there was an excellent companion website [pbs.org].

    If that doesn't answer your questions, well... there's always Wikipedia [wikipedia.org]. /I feel like a Karma whore linking to wikipedia, mod me as you see fit..
    • by zerocool^ ( 112121 ) on Wednesday September 14, 2005 @01:02AM (#13554320) Homepage Journal

      The distance is only barely within the reaches of the observable universe.

      I remember hearing this phrase before, and hearing an explanation, but it didn't make sense. Can you explain this in idiot terms? Something about some things are never actually going to get to us because they're too far away, and that represents the boundries of our reachable universe?

      ~Will
      • by Propagandhi ( 570791 ) on Wednesday September 14, 2005 @01:17AM (#13554394) Journal
        The observable universe is the total volume of the universe from which light could have reached us since the beginning of said universe (the big bang or whatever).

        In other words, as you get farther away from our point of observation (Earth and the area immediately around it) you eventually reach a point in space which is so far from us that light could not have reached us. Assuming that nothing can move faster than the speed of light, this sphere would include everything that could have possibly affected us since the beginning of the universe. Ugh. I hope that makes sense, and I hope I didn't screw that up.

        As usual Wikipedia has more information: Cosmic Light Horizon [wikipedia.org] and Obxervable Universe [wikipedia.org]
        • Ok, so, according to wikipedia, if something happened in the universe 78 billion light years away, it would just now be reaching earth, and if it happened 79 billion light years away from earth, we wouldn't know about it yet.

          And then, it's argued that everything beyond this horizon doesn't exist? So, the universe (according to our understanding) is a constantly growing sphere with earth in the center?

          It just seems wierd. I mean, I know that scientifically, if you can't observe something, for your given sy
          • by Propagandhi ( 570791 ) on Wednesday September 14, 2005 @01:27AM (#13554438) Journal
            So, the universe (according to our understanding) is a constantly growing sphere with earth in the center?

            No, no. That's the key difference between the observable universe and the actual universe itself. The observable universe is just the part of the universe we can actually see/be directly affected* by.

            Sorry, I think I left a few "observables" out of my original reply. You're absolutely right, there's still a universe beyond the observable universe. Problem is, by the time you get to that part of the universe it will have become part of the observable universe (because you can't go faster than the speed of light).

            Important note: as you move your theoretically observable universe changes. So the observable universe for your hypothetical Enterprise would be different from ours, as it would be able to see light which had not reached Earth.
        • Light travels at C in a perfect vaccuum, but the early Universe was quite definitely more crowded than it is today. In consequence, although C would have been the same (the speed of light in a vaccuum is the speed of light in a vaccuum, no mater what space is doing), light itself would have travelled fractionally slower because it had a denser medium to travel through.

          In consequence, although the absolute upper limit of the observable Universe is C * (age of Universe), the actual upper limit must be lower t

      • by Michael Woodhams ( 112247 ) on Wednesday September 14, 2005 @01:41AM (#13554478) Journal
        Here's the simple answer:

        About 13.5 billion light years ago, the universe changed from being opaque to photons to being transparent (an event inappropriately called "recombination"). No photon emitted earlier than this time could reach us, so we cannot observe further than about 13.5 billion light years away. (The photons emitted at that time are the cosmic microwave background.) So the observable universe is 13.5 billion light years in radius. A billion years from now, it will be 14.5 billion light years in radius.

        However, it gets more complicated: the universe is expanding, so the space that photon travelled through has got bigger in the meantime.

        Imagine two points in the universe. Because the universe is expanding, the distance between them is increasing with time. The rate at which the distance increases is a velocity (which you can think of as causing the red shift of distant galaxies.) Hubble's law says this velocity is proportional to the distance between them. If they are sufficiently distant, the relative velocity is greater than the speed of light.

        So (for example) imagine this is twice the speed of light. A photon emitted from one point travels towards the other. After one year, it has travelled one light-year, but the points have got two light-years further apart - clearly it will never arrive. These two points are not in each other's observable universes. The edge of our observable universe are the points which have a recession velocity equal to the speed of light.

        The discussion above assumes no acceleration. Of course, astronomers from Hubble onwards knew there would be acceleration, but it wasn't until the mid 1990s that we could measure it.

        It turns out, contrary to general expectation, that the expansion of the universe is now accelerating. This means that as time goes on, points don't have to be so far apart before their recession velocity exceeds the speed of light, so in a sense the observable universe is getting smaller. (In the sense that points that were within our observable universe in the past are no longer so. But remember that the points are always getting further apart - the radius of the obserable universe is increasing linearly with time.)

        I am an ex-astronomer, not a cosmologist. There may be subtle errors in the above, but I hope not.
        • I was with you until this:

          relative velocity is greater than the speed of light

          From what I recall of physics this is not possible, since the speed of light is the limit regardless of your frame of reference. The fastest anything can move away from you is the speed of light, but in order to do that it would have to have infinite energy.

          If someone can clarify I'd love to hear it, because I've never been able to quite wrap my brain around cosmic boundries either.

  • How do we know the universe is 13.7 billion years old? It was recently discovered that the universe's expansion is accelerating as time goes by. Assuming this change in acceleration has been the case all along, doesn't that really fudge with the numbers we used to estimate the universe's age?
    • by Peyna ( 14792 ) on Wednesday September 14, 2005 @12:42AM (#13554211) Homepage
      How do we know the universe is 13.7 billion years old? It was recently discovered that the universe's expansion is accelerating as time goes by. Assuming this change in acceleration has been the case all along, doesn't that really fudge with the numbers we used to estimate the universe's age?

      There are many ways to estimate the age of the universe, not all of which involve calculating the expansion of the universe.

      http://www.astro.ucla.edu/~wright/age.html [ucla.edu]
    • There are three types of questions: The ones you ask your parents before moving from home, the kind you take to Google, and the kind you just look up: http://en.wikipedia.org/wiki/Age_of_the_universe [wikipedia.org]
    • How do we know the universe is 13.7 billion years old? It was recently discovered that the universe's expansion is accelerating as time goes by.

      I think a better way to describe things is that some evidence was recently discovered which may be interpreted as suggesting that the universe's expansion is accelerating. As our understanding of the universe changes frequently (for example, the idea of a Big Bang was controversial when I was young), it seems to me to be too soon to say anything definite. The idea
  • by No Salvation ( 914727 ) on Wednesday September 14, 2005 @12:39AM (#13554194) Homepage Journal
    Wow, Slashdot really dropped the ball on this one, this news is 13 billion years old.
  • I like to cruise around in Celestia [celestiamotherlode.net], but I can't find models on a scale larger than galaxies. The "sky show" I saw at the Hayden Planetarium (or whatever they call it now, "Rose" something) last year, a "zoom out" from NYC to "the biggest picture" of the whole Universe, looked a lot like a Celestia animation. Is there some kind of model I can run on my Linux machine to cruise the *whole* universe? To look at those several degrees of "superstructures" surrounding us, without that annoying 30min time limit, o
    • Re:You Are Here (Score:3, Interesting)

      by dpp ( 585742 )

      The software you saw at the Hayden might have been something to do with Partiview [haydenplanetarium.org]:

      • It's hard to tell at first, because Partiview is so much slower on a PIII/800/i810 cheapo to which I downloaded it, compared to the Hayden, or even Celestia on that cheapo. But the fonts look different (though maybe I can change the fonts). When I can figure out how to zap over to the Solar system, the planets might look the same, which could mean the same program is working. In any case, Partiview looks really cool - thanks for pointing it out.

        I am wondering about the source code, inevitably. I don't see i
  • If the distant explosions are caused by aliens, like that Slashdot article the other week claimed? When you think about it though, if it is possible to blow up a solar system, such as in the Star Trek 7 movie, then perhaps this is how we're going to find out we're not alone in the Universe - by observing our neighbours knock down a distant tree [proverbially].
    • If the distant explosions are caused by aliens

      Since they seem to go back to the time that the universe was only 1 billion years old, that is fairly unlikely. Stars back then were too immature to produce enough complex elements thought needed by life. It takes several birth-death cycles for stars to produce non-simple elements, such as carbon.

      Further, even if they did arise that early, having the Cosmic Nuke back then would almost certainly have resulted in more noticable changes. One could argue that the
      • You're probably right about not being enough complex elements, unless we're wrong about how matter is organized, or pops into our universe.

        "Most wars produce clusters of weapon usage, near the front lines. These so far seem random."
        Unless the physics of the universe only permit solar destruction in a particular way, and so each advanced species always will eventually come to the same conclusion, and possibly same end. Or the star destroying alien race(s) have almost always existed, and can travel vast dist
      • It's an interesting concept though: look for aliens by trying to see them blow the shit out of each other.

        I mean, what would be the effects of a nuclear war, for instance? Given that we came pretty close to lobbing missiles at each other over Cuba, you'd expect that a reasonable number of civilizations would engage in nuclear exchanges. Is clusters of hydrogen bombs going off simultaneously going to be something we could pick up from hundreds of light years away? Of course, such events would be brief... an

        • I mean, what would be the effects of a nuclear war, for instance?

          It'd sting a bit at first...

          There would be next to nothing detectable at astronomical distances from a nuclear war, and the inevitable fall of the (un)civilisations which participated would be likely to prevent them being involved in any sort of astronomy for a long time afterwards.
        • It's ironic that GRBs were first discovered by the military using systems designed to detect nuclear explosions. They turned the system on and got a steady stream of hits, except they weren't coming from Earth. Kind of interesting.
    • 13 billion years ago there wouldn't have been any aliens. Unless they were based on hydrogen and helium, which doesn't seem very likely. But hell, it's probably not too much of a stretch for star trek.
      • Actually, there seem to be quite a high abundance of elements seen in quasars at these high redshifts. It's probably from very rapid evolution of many generations of stars very quickly in the cores of the first massive galaxies. The lifespan of a massive type O star is only a million years, and a billion years is plenty of time. There are some other subtle issues, but the high-redshift quasars show emission lines indicative of plenty of metals.

        Having said all that, the environments in which the element
    • If the distant explosions are caused by aliens

      It was caused by the Vogons. I read about it in the meeting minutes of a planetary planning meeting somewhere in around Alpha Centauri awhile back.
  • by mbrother ( 739193 ) * <mbrother@uwyoWELTY.edu minus author> on Wednesday September 14, 2005 @12:44AM (#13554224) Homepage
    I *think* we observed, or tried to observe, this burst from our local observatory WIRO. At its high redshift, we probably just got limits with the optical camera that was on the telescope. I'll have to check with my student Cassandra Paul who was on and targeted a burst last week. They released some kind of circular.

    As a quasar guy, I'm excited about this result but happy a quasar still holds the redshift record.
    • The source will turn out to be (angularly speaking) right next to a nearby Seyfert galaxy that has an improbable number of other particularly bright quasars clustered around it. The other quasars' redshifts will be found to decrease with angular distance from the galaxy.
  • from 13 billion light years away

    If my physics class serves me correct, that makes this event happening around 13 billion years ago.

    Which ends up around Sept6, 12999997995 BC.

    Considering that light years = amount of distance light travels in one year, which is alot.
    • So, this happened 13 billion light years away, and therefore 13 billion years ago (assuming that gamma rays travel at the speed of light in a vacuum). How is it that we arrived at this point, here on earth, to observe this event *13 billion years* ahead of the light from the event? Especially if the universe itself is only between 13-15 billion years old?

      Is the earth, our solar system, and the Milky Way travelling faster than the light from the Big Bang, then slowing down enough for light from this even

      • Re: (Score:3, Interesting)

        Comment removed based on user account deletion
      • Re:Old news (Score:4, Informative)

        by Guppy06 ( 410832 ) on Wednesday September 14, 2005 @02:12AM (#13554598)
        You're thinking "hand grenade in a vacuum." There was no space-time before the Big Bang, that's what it created. We're not racing away from everything, the space-time between us is spreading out. The two-dimensional analogy used in Sphereland is that of the universe being the surface of a balloon that's being inflated.

        This is why the cosmic background radiation, which is a relic from the Big Bang, is visible in all directions with the same intensity.
  • by Chairboy ( 88841 ) on Wednesday September 14, 2005 @12:44AM (#13554228) Homepage
    In other news... HULK SMASH!
    • Whomever modded this 'offtopic' obviously wasn't paying attention - how is a Hulk joke in a thread about a Gamma ray burst offtopic? I found this comment by specifically looking for Hulk references. I had been planning on saying something along the lines of :

      "The scientist who spotted this phenomenon has developed strange mutations recently, and sold the movie rights to his story, on the condition that the movie suck as hard as possible."

      Thanks for ruining it for me.
  • Grammar Whore (Score:4, Informative)

    by Anonymous Coward on Wednesday September 14, 2005 @12:58AM (#13554296)
    ahem. Farthest Gamma-Ray... Farthest . 'Further' is a definition of degree. 'Farther' is a measure of distance.
    • Re:Grammar Whore (Score:2, Informative)

      by Anonymous Coward
      There are certainly many people, especially in the US, who observe that distinction. However, there are also many people who do not make a strict distinction between 'farthest' and 'furthest'. I challenge you to find a dictionary that doesn't accept the usage of 'furthest' for distance comparison.
  • by gardyloo ( 512791 ) on Wednesday September 14, 2005 @01:04AM (#13554331)
    ...just Sun's Bold New Ad Campaign.
  • Stupid Sun (Score:3, Funny)

    by Helpadingoatemybaby ( 629248 ) on Wednesday September 14, 2005 @01:08AM (#13554354)
    I just read this article:

    Sun's Bold New Ad Campaign!

    Why post it twice? We already know they're trying to get our attention. Heck, they're even running ads on tv. Although now it makes sense now why Sun's Ad campaign was refused --

    "This is a gamma ray burst! We can't air this! We'll kill all our viewers!"

    Stupid McNealy. He'll kill us all.

  • by TheLoneDanger ( 611268 ) on Wednesday September 14, 2005 @01:10AM (#13554364)
    Here's SWIFT explained through a song [astrocappella.com] by some astronomers who also sing a capella. Much more entertaining than RTFA.
  • from the article:

    "Swift detected the burst and relayed its coordinates within minutes to scientists around the world. Reichart's team discovered the afterglow using the Southern Observatory for Astrophysical Research (SOAR) telescope atop Cerro Pachon, Chile."

    There just happened by chance to be a deep space optical telescope available for chasing after this event? I've always thought one needed to book time at observatories due to the high ratio of astronomers to available telescopes. How is it they
    • by jd ( 1658 ) <imipak@ y a hoo.com> on Wednesday September 14, 2005 @02:05AM (#13554571) Homepage Journal
      SWIFT is a space-based telescope designed specifically to chase gamma-ray bursts. It has amazing thrusters, capable of spinning the telescope faster than anything else we have in space.


      My understanding is there's a low-res, very wide angle gamma-ray detector that they can use to scan vast sections of the sky. If the computers see anything interesting, they spin the probe to get a better look. If it's still a strong candidate, it then notifies anything and everything on Earth that is interested in such events.


      The problem used to be that, precisely because they had to book telescopes and because telescopes are rather unwieldy, even if they saw something, it was too late to get an accurate enough fix to see what the cause was.


      SWIFT was designed to solve this problem. In fact, it has discovered far more bursts than the astronomers were expecting and it started detecting them far sooner. (They got half-drowned in notifications, during the test and burn-in phase.)


      So far, it has been an outstanding success - second only to Hubble, in the sense that Hubble generates better pics for the press and the average space geek. As far as I know, SWIFT was not designed to really record much in the way of actual hard data (other than location), it was more an early-warning system for giant space explosions. That is partly how it works so fast, but with the pitfall that it means that you HAVE to have additional telescopes available, if it does detect something.

      • Swift (not an acronym, so don't capitalize all of the letters) does have a wide field of view gamma-ray telescope. The interesting thing is that it also has a narrow field of view x-ray telescope, as well as a narrow field of view UV/optical telescope on board. This allows the wide field of view instrument to find the burst, then have the telescope slew to position to observe it with the x-ray and UV/optical scopes.
    • by mbrother ( 739193 ) * <mbrother@uwyoWELTY.edu minus author> on Wednesday September 14, 2005 @02:36AM (#13554712) Homepage
      We've had NASA support for GRB followup at Wyoming's observatory, WIRO. We have someone on call every night who gets an alert seconds after SWIFT localizes a GRB. They in turn call the WIRO observers on that night who finish their current exposure and then point at the GRB field. When everything is working, and the right instruments are on (e.g. imagers), and the weather is clear, we can start taking data within five minutes of the GRB. It's kind of cool, especially given that the system is not robotic.

      The space telescopes, in general, are much more difficult to reprogram quickly aside from the systems like SWIFT designed to detect these GRBs.
      • But if a GRB only lasts an average of 10 seconds (according to the article), what good does this do anyone? Even five minutes reaction time would have been too much for this record-breaking event (200 seconds).
  • Earthlings, say cheese! *Flash* Mr. Alien, your film developing estimated time: 26 billions years and 1 hour.
  • Mind Blow. (Score:5, Interesting)

    by hot_Karls_bad_cavern ( 759797 ) on Wednesday September 14, 2005 @02:15AM (#13554613) Journal
    I am a computer engineering kid. Sexy hardware gets me hot, tight software that climbs up to a level i've not pondered is sexy to me ... or even down to a level i don't play in.

    But i have to ask, do you ever just look at the sky at night?

    Do you? Do you really sink deep into your mind the vast firestorm that goes on above your head every day and nigh? Do you look at the stars and ... just for a second imagine the roiling, nuclear fire that churns inside each one ... the amount of matter transformed into energy by each one, each second you watch?

    Do you?

    Break your mind for a second and imagine the scale of this place your little planet wanders around .. and marvel your face off.
  • so I hopped outside and grabbed the old lookin lenses and saw it plain as day. It looked a lot like our sun .... ow my eyes hurt
  • There has been an incident on Praxis. However, everything is under control, we have no need for assistance. Obey treaty stipulations and remain outside the Neutral Zone. This transmission ends now.
  • Let's see...
    13.7 billion minus 13 billion is 700 million.

    So, this thing blew up 700 million years after the big bang. Matter doesn't travel faster than light, supposedly, so this thing blew up *no more than* 700 million light years from where the big bang occurred, right?

    But... if it supposedly happened 13 billion LY away, that makes the center of the universe 12.3 billion LY away from us, at most (assuming *we* are moving away from the center at light speed). Assuming we and this explosion were on opposite
    • by rubycodez ( 864176 ) on Wednesday September 14, 2005 @10:51AM (#13557196)
      you have the wrong idea of "the center of the Universe". that's a meaningless phrase. We are at the center of our observable universe, but the universe as a whole is expanding, and you could call any body you wish the "center", and if you were located there you would see the rest of the universe moving away from you.

Understanding is always the understanding of a smaller problem in relation to a bigger problem. -- P.D. Ouspensky

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