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Most Extreme Gamma-Ray Blast Yet Detected

Soulskill posted more than 5 years ago | from the in-a-galaxy-far,-far-away dept.

Space 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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128 comments

Flash me? (1)

Z00L00K (682162) | more than 5 years ago | (#26939043)

And this isn't a Men in Black flashing device?

Re:Flash me? (2, Funny)

Tubal-Cain (1289912) | more than 5 years ago | (#26939095)

No, just some swamp gas.

Re:Flash me? (0)

Anonymous Coward | more than 5 years ago | (#26939111)

It was just a training exercise.

Re:Flash me? (0)

Anonymous Coward | more than 5 years ago | (#26939141)

That "flash" you thought you saw was just the light of the sun, reflected off of Venus.

WHAT'S THE SCOUTER SAY ABOUT THIS SUPERNOVA? (5, Funny)

Anonymous Coward | more than 5 years ago | (#26939047)

"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~

Re:WHAT'S THE SCOUTER SAY ABOUT THIS SUPERNOVA? (2, Funny)

Anonymous Coward | more than 5 years ago | (#26939137)

best dbz call ever

Re:WHAT'S THE SCOUTER SAY ABOUT THIS SUPERNOVA? (0)

Anonymous Coward | more than 5 years ago | (#26939569)

Indeed Brian Drummond > Chris Sabat

Re:WHAT'S THE SCOUTER SAY ABOUT THIS SUPERNOVA? (0)

Anonymous Coward | more than 5 years ago | (#26939573)

WHAT?! 9000?! THERE'S NO WAY THAT CAN BE RIGHT!

Someone had to do it.

And screw the caps filter.

Re:WHAT'S THE SCOUTER SAY ABOUT THIS SUPERNOVA? (1)

KibibyteBrain (1455987) | more than 5 years ago | (#26940771)

I was confused by this though. Usually explosive yields and such impulsive events are given in terms of energy. I'm not sure what to make of the power of a burst. After all, the power of a pulse is zero except when integrated over a limited time range, and without being given an interaction time, this claim is sort of ambiguous.

coloured dots!!! (1)

enter to exit (1049190) | more than 5 years ago | (#26939057)

The website comes with a gif animation of coloured dots!!!

WOAHH!!!

This is called humour, oh Spock descendant mods

yes i see the time problem in my statement

Re:coloured dots!!! (3, Insightful)

MichaelSmith (789609) | more than 5 years ago | (#26939271)

What I wanted to see was a graph with time on the horizontal axis and energy on the vertical axis. That would give me a better feel of what the burst actually did.

And make it relative! (1)

Gazzonyx (982402) | more than 5 years ago | (#26939349)

I'm assuming you'd like the logarithmic scaled version! :)
I'd go one further. That very same graph with a third axis (axee? axen? Arg!) that shows this burst/time graph relative to an energy source I can somewhat comprehend. Maybe the projected output of an average star over that same time frame.

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

Re:And make it relative! (3, Informative)

yotto (590067) | more than 5 years ago | (#26939407)

That very same graph with a third axis (axee? axen? Arg!) that shows this burst/time graph relative to an energy source I can somewhat comprehend.

The plural of axis is axes.

That said, you're talking about a single one (the third in a set, but it's still singular) so axis is correct.

Re:And make it relative! (5, Funny)

Antique Geekmeister (740220) | more than 5 years ago | (#26941059)

And the plural of axes is chainsaw.

Re:And make it relative! (2, Interesting)

MichaelSmith (789609) | more than 5 years ago | (#26939437)

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.

Re:And make it relative! (-1)

Anonymous Coward | more than 5 years ago | (#26940661)

If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.

In that case please mod me down so I know you agree.

Re:coloured dots!!! (1)

daemonburrito (1026186) | more than 5 years ago | (#26939429)

http://arxiv.org/abs/0902.0761 [arxiv.org]

Submitted by the leader of the team working with GROND.

Re:coloured dots!!! (1)

MichaelSmith (789609) | more than 5 years ago | (#26939609)

Thanks.

Re:coloured dots!!! (2, Interesting)

boot_img (610085) | more than 5 years ago | (#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:coloured dots!!! (1)

History's Coming To (1059484) | more than 5 years ago | (#26940275)

Ok, lets try this....

If a tonne of TNT goes "Boom!", and six tonnes goes "Booooooom!" (etc) then to type this noise out would take 1,000,000,000,000,000,000,000,000,000,001 o's.

Nope. Doesn't help either.

Re:coloured dots!!! (1)

RicktheBrick (588466) | more than 5 years ago | (#26940715)

This numbers are way to large to mean anything to me. What interests me is if this explosion had occurred anywhere in the milky way galaxy and the energy was directed at earth, would we still be here discussing the matter?

Re:coloured dots!!! (1)

the_other_chewey (1119125) | more than 5 years ago | (#26940799)

What interests me is if this explosion had occurred anywhere in the milky way galaxy and the energy was directed at earth, would we still be here discussing the matter?

Depends. Is slashdot accessible from the afterlife?

Re:coloured dots!!! (2, Informative)

the_other_chewey (1119125) | more than 5 years ago | (#26940779)

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

Not quite. You are thinking of the sowjet "Tsar Bomba" [wikipedia.org] - with an estimated
blast of about 50Mt TNT-equivalent. That would be 50e6, or 5*10^7.

This factor of ten of yours of course doesn't change the fact that the amounts of energy involved in cosmic
explosions are mindbogglingly huge.

Re:coloured dots!!! (2, Informative)

hwyhobo (1420503) | more than 5 years ago | (#26939281)

gif animation

Actually, it is worse. It is a 6-second .mov Quicktime movie, all 7 MB of it. Considering it is a 6-second movie of colored dots, it would have been a lot more efficient to represent it in a different format. Perhaps an animated GIF?

Re:coloured dots!!! (1)

MadnessASAP (1052274) | more than 5 years ago | (#26939319)

Your tax dollars at work eh? Paying for NASAs servers to withstand a Slashdotting of an excessively large movie.

Attn Moderators: You Suck (-1, Troll)

Anonymous Coward | more than 5 years ago | (#26939059)

Lick my balls you brainless fucking retards.

Only a coward shit stain mods people down when an article gets old

I just went from +5 to +2 because of shit stain moderators.

fuck you

Re:Attn Moderators: You Suck (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#26940853)

Dude, what's your account nickname? I'll mod you up...JACKASS!

They mocked me... (0)

Anonymous Coward | more than 5 years ago | (#26939067)

when I said we all need aluminum foil hats and sunblock. Just because I couldn't tell them when we'd need these things, doesn't mean I wasn't right!

3s (1)

doyoulikegoatseeee (930088) | more than 5 years ago | (#26939079)

wea

Feh... (0)

Anonymous Coward | more than 5 years ago | (#26939091)

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.

That's barely 6 Libraries of Congress. Astronomers and physicists notoriously underestimate the power of good fiction.

Big Bang (1)

Gresyth (1103851) | more than 5 years ago | (#26939121)

so they finally found it, eh?

Re:Big Bang (1)

symbolset (646467) | more than 5 years ago | (#26939415)

Not even close. The universe extends so far in every direction that no matter where you look, you get objects receding from you at the speed of light.

On the upside though, congratulations! You are once again at the center of the known universe.

Re:Big Bang (3, Informative)

boot_img (610085) | more than 5 years ago | (#26939903)

No, this was just a little Bang. The big one, we had already found. You can see a picture here [nasa.gov] .

how do they know (1)

timmarhy (659436) | more than 5 years ago | (#26939157)

i've always wondered how they know the size and distance of these objects. short of running a tape measure out, how the hell do you calculate the size of something an unknown distance away?

Re:how do they know (1, Informative)

Anonymous Coward | more than 5 years ago | (#26939191)

Parallax and red shift, I would imagine. They know the speed of light, and the rate (roughly) that red-shifting happens. Parallax measurements allow them to determine how far away it is to at least a modicum of accuracy.

Note: The above is a guess, but it seems plausible.

Re:how do they know (1)

Sorny (521429) | more than 5 years ago | (#26939195)

Parallax and redshift perhaps?

Re:how do they know (2, Interesting)

Snowblindeye (1085701) | more than 5 years ago | (#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.

Re:how do they know (2, Informative)

Spy Handler (822350) | more than 5 years ago | (#26939313)

parallax only works for stars very close (astronomically speaking) to us... few dozen light-years at most. Even then they have to use the whole width of earth's orbit around the sun, taken 6 months apart, to calculate the parallax.... closing your left eye then your right eye aint gonna cut it for measuring light-year distances :P

Redshift is how they measure galaxy distances, and by some process they determine that this gamma ray burst occurred in galaxy X, so that's how far they come up with the distance here. I think, I haven't RTFA :-/

Re:how do they know (3, Informative)

daemonburrito (1026186) | more than 5 years ago | (#26939603)

The host or counterpart galaxy was too faint (the GRB was 12.8Gly away, and models predict that the host galaxy wouldn't be detectable). But apparently, there is now enough confidence in the models for GRBs to get a good fix on the distance anyway. It's awesome that they can do this without observing a host galaxy now.

The same team that measured this also confirmed the most distant GRB to date last September, and this is within the most distant 5% of observed GRBs.

Arxiv paper [arxiv.org]

Re:how do they know (0)

Anonymous Coward | more than 5 years ago | (#26939201)

A few possibilities:
If they know the spectrum shape they should be looking at, they can see how far red shifted the spectrum is. The farther away and object is, the bigger the red shift due to the expansion of the universe. Not sure if this is how they're doing it.

They also might be able to see some sort of gravitational lensing effect (some photons swinging around a nearby blackhole or something) as well, which might allow them to triangulate the source.

Re:how do they know (0)

Anonymous Coward | more than 5 years ago | (#26939247)

The real question then is... how did the know the spectrum shape?

Re:how do they know (1)

daemonburrito (1026186) | more than 5 years ago | (#26939555)

The spectrum shape and afterglow over time are predicted by models. Here's one cited by the J. Grenier et al. paper on arxiv: http://www.journals.uchicago.edu/doi/abs/10.1086/518996 [uchicago.edu] .

Here's the J. Grenier (the GROND leader) paper on arxiv: http://arxiv.org/abs/0902.0761 [arxiv.org]

Re:how do they know (1)

doti (966971) | more than 5 years ago | (#26939813)

So is the weather, and the stock market.

Re:how do they know (2, Interesting)

Guido von Guido (548827) | more than 5 years ago | (#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.

Re:how do they know (0)

Anonymous Coward | more than 5 years ago | (#26941037)

Don't you have any Wikipedia articles? Hell, everybody knows that is the only authoritative source of information.

Re:how do they know (2, Interesting)

robbiedo (553308) | more than 5 years ago | (#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 (2, Informative)

MichaelSmith (789609) | more than 5 years ago | (#26939243)

One of the articles I read about this event talks about a technique which relies on the way light between the source and us is absorbed by dust along the path which the light traverses. Low energy photons are absorbed at a different rate to high energy photons. Measuring the spectrum at our end can tell you how much dust is between us and the light source. This gives astronomers an estimate of distance.

GROND (2, Informative)

daemonburrito (1026186) | more than 5 years ago | (#26939327)

In this particular case, it was this [eso.org] .

Method is explained a little in the eso.org link, but here's a wikipedia article, too: http://en.wikipedia.org/wiki/Photometric_redshift [wikipedia.org] .

Also, awesome Tolkien reference apparently acknowledged by Jochen Greiner.

Re:GROND (1)

NewbieProgrammerMan (558327) | more than 5 years ago | (#26940161)

Wow, that's obscure [wikipedia.org] !

Re:how do they know (5, Informative)

DamienRBlack (1165691) | more than 5 years ago | (#26939433)

i've always wondered how they know the size and distance of these objects. short of running a tape measure out, how the hell do you calculate the size of something an unknown distance away?

The chain of logic is vast and complex, but I'll try to summarize:

1) First, we used radar and the speed of light to figure out the distances of things in our solar system. These calculations helped us figure out the diameter of the Earth's orbit, which is used in the next step, parallax.

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.

3) Once we could figure our how far away nearby stars are, we began focusing in on types of stars that have fairly consistent outputs of energy in comparison to their other measurable traits, such as color. We call these consistent types of stars (and other astronomical objects) standard candles.

4) Once we are sure that these standard candles do indeed have consistently predictable outputs, we can guess how far away stars of these types are by noting that luminosity (total light output) and apparent brightness are related by a simple inverse distance squared relationship. This lets us estimate the distance to any type of star that has a fairly estimable luminosity.

5) After we have our standard candles mapped out in space, we can note the absorption lines in the light spectrum which indicates various types of dust and gasses. With this data we can make a rough map of where dust and gasses are floating around. This map will let us look at light from stars and objects that aren't standard candles and figure out how far away they should be to account for the absorption lines we see in their light spectrum.

6) After mapping out many of the nearby galaxies using supernovae as our key standard candle, we notices that is seems that there is a linear correlation between how far away an object is and how fast it is moving away from us (we can tell how fast an object is moving away from us using red-shift). This observation seems to show that the universe is expanding, but more important to the discussion at hand, it gives us another tool with which to estimate and map the distances of objects -- this time at any arbitrary distance.

Using the many of the above methods we can get estimates for how far away objects are, but the margin of error is huge because of all of the assumptions we've made. Plus of minus a magnitude or two is considered fairly precise in astronomical terms. This might have been more of an answer than you bargained for, but there you have it.

Re:how do they know (5, Insightful)

ergean (582285) | more than 5 years ago | (#26939599)

This is why I come to /. once in a thousand comments there is one like this. Thank you!

Re:how do they know (4, Informative)

ConanG (699649) | more than 5 years ago | (#26939605)

I don't think you made the part about standard candles very clear, so I'll elaborate on that point.

The term doesn't refer to a specific type of star. Standard candles are any stellar objects that have some quality that allows them to be used to measure distance.

One of the most famous examples are Cepheid variable stars. These stars all vary in brightness over some predictable period of time. There is a relationship between how fast they "pulse" and how bright they are. The faster they pulse, the dimmer they are (in absolute terms). If one is pulsing really slow, and it looks dim (relatively speaking), it's probably very far away since it should be relatively bright. If it looks bright and pulses quickly, it's probably close by since they don't get very bright (absolutely speaking).

Other standard candles include planetary nebula, supergiants, globular clusters, H II regions, and supernova. Each of them has a different maximum range over which they can be detected, but there is some overlap. The ones in the overlapping regions are used to calibrate the distances for the rest.

Re:how do they know (1)

Janek Kozicki (722688) | more than 5 years ago | (#26939611)

yep, thank you! ...and I wonder why this story is tagged !etacarinae

Re:how do they know (1)

daemonburrito (1026186) | more than 5 years ago | (#26939719)

I hope I won't get whooshed for this, but the !etacarinae tag is because the popular science articles said it was in the direction of the constellation Carina. There is a famous hypergiant in that direction, about 7.5Kly away from us called Eta Carinae [wikipedia.org] , which is expected to supernova in the near future (astronomically near, anyway) and produce a GRB.

GP's post is fine and all, but the determination of the distance of this is just as interesting as its extreme intensity. The host galaxy was too faint to be detectable. That they can determine the distance is due to the predictive power of the current models for GRBs and the network of instruments on earth and in space that can quickly focus on an event.

The determination of the distance and intensity is the actual accomplishment here. http://arxiv.org/abs/0902.0761 [arxiv.org]

Re:how do they know (1)

Genda (560240) | more than 5 years ago | (#26940025)

For those not familiar with Eta Carinae, you need to check out the Eta Carinae nebulae (one of the largest nebulae of it's kind in our neck of the galaxy, and the star itself which puffs out huge amounts of gas and dust. The current dual lobed cloud surrounding the star if brightly illuminated by it, and referred by astronomers as the Homunculus (latin for little human or puppet.) Because the cloud seen through a telescpe looks vaguely like a little doll.

If this star does go with a gamma ray burst, and if one of the beams is pointed directly at earth, it will cause us to have a very bad day.

Re:how do they know (1)

ArmchairGeneral (1244800) | more than 5 years ago | (#26940151)

Damn, well put. I've indeed learned something useful today, thank you very much.

Re:how do they know (1)

syousef (465911) | more than 5 years ago | (#26940403)

Parent is essentially correct and thorough but one thing I'll add is the importance of supernova as standard candles.

A certain type of supernova - Type Ia [wikipedia.org] is always going to peak at the same absolute brightness because of the physical process involved. It is the result of one star - a white draw - drawing in matter from another star until the white dwarf reaches a mass where it can no longer keep itself from collapsing. As a result it implodes and bounces back as a spectacular supernova explosion. Since the point at which this mass is too much for the star to hold itself up against gravity is consistent (determined by the physics) the brightness of each type Ia is almost exactly the same.

So now we just need to measure the apparent brightness of one type Ia supernova, and knowing the distance by other means we work out it's absolute brightness. If we see another type Ia (and we can tell the type by looking at the spectra) we know it's absolute brightness, measure it's apparent brightness, and with a simple calculation we get a pretty good estimate of how far away it is. We can now work out the distance to incredibly distant objects because the supernova explosions are so big they're seen clearly in distant galaxies.

Re:how do they know (1)

John Hasler (414242) | more than 5 years ago | (#26940433)

> 1) First, we used radar and the speed of light to figure out the distances of things in
> our solar system. These calculations helped us figure out the diameter of the Earth's
> orbit, which is used in the next step, parallax.

No. First we used Newton's laws and geometry to figure out the distances of things in our solar system. No radar needed. The first quantitative estimates of the speed of light were made using the known motion of and distance to Jupiter's moon Io.

Need for a bigger parallax? (3, Interesting)

tjstork (137384) | more than 5 years ago | (#26940705)

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.

Re: 3d map of the galaxy (3, Interesting)

andersa (687550) | more than 5 years ago | (#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 [esa.int] 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.

Re:how do they know (0)

Anonymous Coward | more than 5 years ago | (#26941563)

You are well written and made this info easy enough to understand. Going along I couldn't help but hear it in the voice of Neil deGrasse Tyson. Well done.

Re:how do they know (1)

boot_img (610085) | more than 5 years ago | (#26939911)

The observed redshift (4.5 in this case) and the Friedmann equation [wikipedia.org] .

Re:how do they know (1)

jo42 (227475) | more than 5 years ago | (#26941085)

WAG - Wild Arsed Guess.

From the chan (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#26939171)

"Fermi, what does the scouter say about its power level?"
Fermi "It's over 9000!

alternate... (2, Funny)

800DeadCCs (996359) | more than 5 years ago | (#26939209)

In an alternate galaxy long long ago...

Emperor palpatine went senile, and every time they fired the death star superlaser, insisted that darth vader pull his finger.

Re:alternate... (1)

MichaelSmith (789609) | more than 5 years ago | (#26939263)

Personally I wonder if somebody was fighting a hot war 12 billion years ago, and occasionally a weapon gets pointed in our direction.

Re:alternate... (1)

Criliric (879949) | more than 5 years ago | (#26939287)

i've always pondered that myself, even just a stray shot from a stellar dog fight, it would be rather interesting and answer some questions for sure

Re:alternate... (1)

Artraze (600366) | more than 5 years ago | (#26939413)

It's a fun idea, but practically speaking, this is just far too powerful. A handful of supernovae worth of energy could fairly easily destroy an entire solar system, so a weapon yielding OVER 9000!!! (sorry) would be severe overkill. And not the fun sort of 'why not' overkill, but the inter-solar equivalent of nuking it from orbit: for when you have to be sure nothing within several hundred light-years survives (and another few thousand ltyr are devastated).

So maybe it'd be more accurate to think of these as a civilization's last ditch effort to take out a horrible nemesis, rather than a simple weapon.

Re:alternate... (1)

bingoathome (1027034) | more than 5 years ago | (#26939539)

Yes but if it was a tightly focused weapon that missed its target 12 billion years ago then it might have only needed to be half a super nova (which is equal to 20 LoC raised to the power of a slashdot meme). Any hooos if you can decimate someone else's 2000 light years of space why not - teach a lesson an' all that.

Alien industrial accident (1)

TapeCutter (624760) | more than 5 years ago | (#26939577)

IIRC it was Arthur C Clarke who, with tounge firmly in cheek, suggested such blasts were in fact alien industrial accidents.

Re:alternate... (1)

ConanG (699649) | more than 5 years ago | (#26939647)

The 9000 figure is assuming that the radiation is spread equally in every direction. A "stellar dog fight" weapon might not work that way. Think of a laser. Focus a lot of energy into a fairly tight beam. It would look a hell of a lot more powerful if someone assumed that same amount of energy was being spread in every direction.

Hulk SMASH puny Gamma-Ray!!!!! (0)

Anonymous Coward | more than 5 years ago | (#26939221)

Hulk SMASH puny Gamma-Ray!!!!!

9000? (-1, Offtopic)

tshetter (854143) | more than 5 years ago | (#26939237)

Weak troll Matt_dk and SoulSkill.


Lame ass meme.

Re:9000? (0, Offtopic)

tshetter (854143) | more than 5 years ago | (#26939275)

Haha, I do not admit failure!!

The meme has clearly spread its insidious influence into the deepest fathoms of our government.

Purge, purge, purge!!!!

Power of Gamma Ray Bursts (4, Informative)

Snowblindeye (1085701) | more than 5 years ago | (#26939245)

My favorite comparison to illustrate the power of Gamma Ray Bursts: A Gamma Ray Burst puts out the same amount of power (while it is bursting) as all the stars in the universe together.

(Usually comparisons made in the media are rather lame, i.e. Libraries of Congress, but this one really impressed me)

Re:Power of Gamma Ray Bursts (0)

Anonymous Coward | more than 5 years ago | (#26939467)

So, in other words... Damn, son!

God is such a show off.

And no-one knows why they go bang. (0)

Anonymous Coward | more than 5 years ago | (#26939257)

Astrophyicists understand supernova pretty well.
But Gamma Ray bursts are a mystery. Actually 3 mysteries, because they been classed into three types the fastest a 1000 times faster than the slower type. Suggestion for the energy source, and how they beam the explosion, have been the collaspe of the inside of a star to a black hole. The supernova of a mirror-matter star (any gamma rays can go straight through the mirror-matter stars outer material), and the magnetic beaming.

Astronomy Feeds [blogknox.com] combined

Re:And no-one knows why they go bang. (1)

Xiroth (917768) | more than 5 years ago | (#26939389)

But Gamma Ray bursts are a mystery. Actually 3 mysteries, because they been classed into three types the fastest a 1000 times faster than the slower type.

Uh, what? Last I checked, there's only one speed that gamma rays can go in a given medium - the speed of light. Are you perhaps referring to frequency differences?

Re:And no-one knows why they go bang. (2, Informative)

Bazman (4849) | more than 5 years ago | (#26939453)

The "speed" is how long the burst lasts for - not how fast the gamma rays go!

Alien Hulk Incoming (1)

V50 (248015) | more than 5 years ago | (#26939273)

Bah, all that star talk mumbo-jumbo. We all know what really happened.

A bunch of aliens just created the Hulk.

Vegeta, what does the scouter say... (0, Funny)

Anonymous Coward | more than 5 years ago | (#26939301)

IT'S OVER 9000!!!

WHAT 9000?!?

nobody's said this yet? (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#26939307)

I guess I'll be the first.
It's over NINE THOUSAAAAAAAAAAAAAND supernovae

Kaboom (5, Funny)

Dracophile (140936) | more than 5 years ago | (#26939321)

Great shot, kid! That was one in a million!

question (3, Funny)

binaryseraph (955557) | more than 5 years ago | (#26939331)

Soooo should I put on the tin foil hat again?

Re:question (1)

mail2345 (1201389) | more than 5 years ago | (#26939343)

Tin foil hats don't shield from gamma ray bursts.
Their unique properties deflect only mind control rays.
Everyone knows that.

To deflect gamma rays, you really need these magnetic bracelets! Only 19.99! They use the power of magnets to deflect the bad stuff in your body!

Let me be the first to say.. (1, Interesting)

RichiH (749257) | more than 5 years ago | (#26939373)

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

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

Kai Hansen commented the news as (2, Funny)

toriver (11308) | more than 5 years ago | (#26939395)

"awesome!"

nice summary (1)

circletimessquare (444983) | more than 5 years ago | (#26939409)

all i can think is

<keanu reeves voice>whoa</keanu reeves voice>

Faulty logic in determining its power? (0)

Anonymous Coward | more than 5 years ago | (#26939499)

In the article, there is this paragraph:

"With the distance in hand, 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. This is a standard way for astronomers to compare events even though gamma-ray bursts emit most of their energy in tight jets."

It would seem, to me, that the rationale used here to determine the power of a gamma ray burst is at odds with the observed behaviour of gamma ray bursts.

Can someone explain why this is?

Shouldn't the report at least contain a caveat that allows for the other case? Or is that far less sesnsational for NASA's press?

It's called "EIRP" (2, Informative)

mangu (126918) | more than 5 years ago | (#26939735)

A common acronym you'll find in engineering and physics texts is EIRP, which stands for equivalent isotropic radiated power. This means you take the direction with the highest intensity of radiation and calculate what would be the total power if it was radiated with equal intensity in all directions.

This system of calculation is very convenient in communications engineering, because you buy amplifiers and antennas separately. Antennas which emit tighter beams are called "high gain", because using one such antenna allows you to use a smaller amplifier to get the same effect at one direction.

In microwaves it's very common to trade off the cost of a smaller antenna against the higher cost of a more powerful amplifier when designing a point to point link. When you calculate the needed signal intensity at the receiver, you represent the result as an EIRP and calculate the loss due to the signal spreading out to get the needed EIRP at the transmitter. Then you check out how much different antennas and amplifiers cost to get the cheapest combination that gives the needed EIRP.

Since radio astronomy uses basically the same formulas, it only stands to reason that astronomers would use the same terminology.

We have witnessed the death of several evolved (3, Interesting)

assemblerex (1275164) | more than 5 years ago | (#26939693)

civilizations, if the odds of other life evolving to advanced civilizations is taken seriously.

Re:We have witnessed the death of several evolved (1)

JamesP (688957) | more than 5 years ago | (#26940197)

I wish I had mod points for this, so true.

They say if a supernova (does its thing) in (apparently very far distance) from earth, we'll all be wiped out.

But again, we're in the urban sprawl of the milky way,

Re:We have witnessed the death of several evolved (2, Insightful)

Anonymous Coward | more than 5 years ago | (#26940875)

Since the explosion was 12.2 billion light years away, and the age of the universe is 13.7 billion years, the objects around it would have got a maximum 1.5 billion years to nurture.
Now, considering the fact that the universe was very violent at that time, there might not have been any possibility of any civilization at all.
Also considering the fact that after sun came into being, life (basic proto microbial) took almost 1.5 billion years, and from there almost 2.5 billion years to reach the current stage, the possibility of any civilization being extinguished by the burst does seem remote.

Re:We have witnessed the death of several evolved (2, Insightful)

jschen (1249578) | more than 5 years ago | (#26941333)

Furthermore, the early universe was much less rich in elements other than hydrogen and helium. Anything we might recognize as an advanced life form almost certainly would require a few generations of star formation to go by first before there's enough heavier elements given off by all the supernovas out there (admittedly, a lot more back then) to give them a chance. That said, it's not out of the question that something evolved that quickly. Sure, it wasn't so fast on earth, but one data point hardly makes for a rule.

Big Bangs... (1)

Talkischeap (306364) | more than 5 years ago | (#26940513)

They are Big Bangs "leaking" into our universe from another.

Like the one the bore our universe.

Betcha'.

Mini black holes which will destroy the Earth (0)

Anonymous Coward | more than 5 years ago | (#26940621)

Did it create any?

So the universe is older than 14 billion years (0)

Anonymous Coward | more than 5 years ago | (#26940733)

If we detected a gamma ray explosion that happened 12.2 billion light years away (12 billion years ago), and it wasn't hopelessly red-shifted, then the universe must be much older than 14 billion years, as the 2 remaining billion years wouldn't have been enough time for Earth and that point in space to "travel" apart so far away from each other while decelerating to the point that their gamma ray explosion can then travel back in our direction and meet us at this time. I think I have a headache now.

That was no collapsing star... (1)

Strake (982081) | more than 5 years ago | (#26940793)

I was just changing my shirt.

"The first gamma-ray burst to be seen in high-reso (1)

braintartare (629755) | more than 5 years ago | (#26940847)

"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." Coincidence? "Little girl don't you know that the stars up above are runnin' on love Little girl don't you know that uh they're blinkin' at you"
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