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Space Science

Most Extreme Gamma-Ray Blast Yet Detected 128

Matt_dk sends in a quote from a story at NASA: "The first gamma-ray burst to be seen in high-resolution from NASA's Fermi Gamma-ray Space Telescope is one for the record books. The blast had the greatest total energy, the fastest motions and the highest-energy initial emissions ever seen. ... Gamma-ray bursts are the universe's most luminous explosions. Astronomers believe most occur when exotic massive stars run out of nuclear fuel. As a star's core collapses into a black hole, jets of material — powered by processes not yet fully understood — blast outward at nearly the speed of light. The jets bore all the way through the collapsing star and continue into space, where they interact with gas previously shed by the star and generate bright afterglows that fade with time. ...Fermi team members calculated that the blast exceeded the power of approximately 9,000 ordinary supernovae, if the energy was emitted equally in all directions."
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Most Extreme Gamma-Ray Blast Yet Detected

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  • Re:how do they know (Score:2, Interesting)

    by robbiedo ( 553308 ) on Saturday February 21, 2009 @03:55AM (#26939215)
    There are an awful lot of assumptions made in astronomical measurements. Numbers that are bandied about have huge margins for error based on a series of interdependent assumptions. Not only is this estimated to be 12 billion light years distant; obviously, this event occurred in the distant past near the beginning of the Universe itself.
  • Re:how do they know (Score:3, Interesting)

    by Snowblindeye ( 1085701 ) on Saturday February 21, 2009 @04:15AM (#26939295)

    Parallax and redshift perhaps?

    Parallax only works to about 1600 light years, which is aprox 1% of the diameter of our Galaxy. And that is with a specialized satellite doing the measurement. There is no way parallax is going to work for something that is 12.2 billion light-years away.

  • by RichiH ( 749257 ) on Saturday February 21, 2009 @04:42AM (#26939373) Homepage

    ..why is this not moderated over9000 (yet)? ;)

    Yah, yah, it's old, but hey. It fits :)

  • by MichaelSmith ( 789609 ) on Saturday February 21, 2009 @04:58AM (#26939437) Homepage Journal

    P.S. - Great sig. I actually LOL'ed.

    Its not mine though. Years ago there was a magazine called Kilobaud Microcomputing. In one issue they ran a funny graphic story called "The man from CPU". It was a detective story built around computer jargon. By the time I realised the value of it my Dad had cleared out the attic and all the old magazines were gone. From time to time I google a few choice keywords in the hope that somebody has put their archives on line and I can recover the article.

    So far it has been no go but I put that line in my sig in the hope it would jog someone's memory and they would have a copy they could put on line for me.

    From memory: few choice lines:

    • That must be the same massive compiler which executed Object ProgRam, our Indian agent.
    • He picked up a nearby filing cabinet and tried to delete me.
    • I flipped the Matre D' two bits. Parity checked out and I was good to go.
    • In a couple of microseconds I was on the other side of town.
  • by assemblerex ( 1275164 ) on Saturday February 21, 2009 @06:43AM (#26939693)
    civilizations, if the odds of other life evolving to advanced civilizations is taken seriously.
  • Re:coloured dots!!! (Score:3, Interesting)

    by boot_img ( 610085 ) on Saturday February 21, 2009 @07:39AM (#26939889)

    "9,000 ordinary supernovae" = 9000 x 10^44 Joules =~ 10^48 Joules.

    According to Wikipedia, 1 ton (do they mean tonne) of TNT = 4 x 10^9 Joules, so this makes 2 x 10^38 tons of TNT equivalent.

    And the largest bomb ever exploded is 5x10^8 tons of TNT.

    So this would be ~ 10^30 of those, or around a million Yotta-bombs.

    Not sure if that helps.

  • Re:how do they know (Score:3, Interesting)

    by Guido von Guido ( 548827 ) on Saturday February 21, 2009 @10:32AM (#26940565)

    So is the weather, and the stock market.

    Bad analogy. We're using these models to do something more along the lines of looking at all that standing water in somebody's backyard about three states away and saying, ah yes, it rained there last night. In other words, they're looking at something that's already happened and attempting to figure out what has already happened. I think we can do this at least reasonably well for both the weather and (to a lesser extent, I suspect) the stock market.

  • by tjstork ( 137384 ) <> on Saturday February 21, 2009 @10:53AM (#26940705) Homepage Journal

    That's enormously interesting.

    It seems to me that, if funding were available, one of the most useful things for astronomy then would be a set of ships sent to "opposite" orbits in the solar system, extremely far from the sun. Given today's technology, the farther you could get a pair of ships orbiting at an extreme distance from the sun - out past jupiter and farther, then, you could extend the range of your parallax measurements, which are fairly direct. You'll never obviously be able to get the whole universe, but you would be able to get more standard candles. Or, are there already enough stars within a thousand light years that you don't need that? A thousand light years is a pretty good chunk of space.

  • by andersa ( 687550 ) on Saturday February 21, 2009 @12:48PM (#26941487)

    2) Once we know the diameter of Earth's orbit, we used parallax to determine the distance to nearby stars. Parallax is a process of triangulation, where we use the earth at two extremes and the star we are looking at as the three points of a triangle. Knowing two angles and one side lets us solve for the distance to the star. But the resolution of our telescopes only lets us use this method with any accuracy for stars in our immediate vicinity.

    This is where the Gaia mission [] will step in and improve things drastically.

    Using distant quasars as fixed beacons, Gaia will collect paralax data to all of the brightest starts in our galaxy and for a huge number of closer stars. With this data we will be able to produce a precise 3d map of our entire galaxy. We will finally be able to see it as a distant observer will see it. It will revolutionise our knowledge of space. I personally think this is the coolest astrophysics project being developed right now.

  • by Kagura ( 843695 ) on Saturday February 21, 2009 @01:09PM (#26941675)

    "Fermi team members calculated that the blast exceeded the power of approximately 9,000 ordinary supernovae, if the energy was emitted equally in all directions." IT'S OVER NINE THOUSAAAAAND~

    I was hoping for a great set of comments to read, but now I have to pick and choose to get to the informative comments--all because of this number. ;(

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