Slashdot Mirror
Most Extreme Gamma-Ray Blast Yet Detected
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."
And this isn't a Men in Black flashing device?
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
"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~
WOAHH!!!
This is called humour, oh Spock descendant mods
yes i see the time problem in my statement
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!
That's barely 6 Libraries of Congress. Astronomers and physicists notoriously underestimate the power of good fiction.
so they finally found it, eh?
Tech Support: "No, sir...clicking on 'Remember Password' will NOT help you remember your password."
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?
If you mod me down, I will become more powerful than you can imagine....
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.
Hulk SMASH puny Gamma-Ray!!!!!
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)
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 combined
Bah, all that star talk mumbo-jumbo. We all know what really happened.
A bunch of aliens just created the Hulk.
Haha, I do not admit failure!!
The meme has clearly spread its insidious influence into the deepest fathoms of our government.
Purge, purge, purge!!!!
IT'S OVER 9000!!!
WHAT 9000?!?
Great shot, kid! That was one in a million!
Athy, athier, athiest.
In this particular case, it was this.
Method is explained a little in the eso.org link, but here's a wikipedia article, too: http://en.wikipedia.org/wiki/Photometric_redshift.
Also, awesome Tolkien reference apparently acknowledged by Jochen Greiner.
Soooo should I put on the tin foil hat again?
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.
If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.
..why is this not moderated over9000 (yet)? ;)
Yah, yah, it's old, but hey. It fits :)
"awesome!"
all i can think is
<keanu reeves voice>whoa</keanu reeves voice>
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
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?
IIRC it was Arthur C Clarke who, with tounge firmly in cheek, suggested such blasts were in fact alien industrial accidents.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
civilizations, if the odds of other life evolving to advanced civilizations is taken seriously.
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.
Basically this wikipedia article talks about a specific instance of using geometry to figure out how far a supernova was. http://en.wikipedia.org/wiki/SN_1987A#SN1987A_distance_and_the_speed_of_light
Did you know 80 to 90% of the moderators on slashdot wouldn't recognize a troll even if one dragged them under a bridge.
They are Big Bangs "leaking" into our universe from another.
Like the one the bore our universe.
Betcha'.
If it don't GO... chrome it. ~ Frank Banks
Did it create any?
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.
This is my sig.
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.
I was just changing my shirt.
"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"
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.
She stopped at a news station. "...results of the special election will be announced as they occur," the announcer said. "Meanwhile on the science front: astronomers report another `inexplicable nova' discovered. That makes seven so far. According to scientists, these novas shouldn't be happening, because they aren't the right type of stars. They--"
Something connected in Quaid's mind. "Oh, my God!" he breathed.
Melina looked at him again. "Something wrong?"
"That news item--those novas--I just realized--" He choked off, not wanting to believe it.
"What's the matter, Doug?" she asked, alarmed.
"Those novas--they're artificial," he said. "That's why they don't seem to make sense. They're seeded, same way as the No'ui seed species."
"I suppose, if the aliens are as powerful as you say," she said doubtfully. "But I can't believe that--"
"Believe it!" he said. "You haven't seen the sheer scale of that reactor! If they can build something like that, and use alien science to make air in a way we couldn't, they can seed a star to go nova!"
"Well, maybe so, if you say so. But what has that to do with this?"
"I told you, they don't pussyfoot! It's all or nothing with them. No second chance."
"Yes, but--"
"The destruct symbol," he said, feeling the horror rise as he spoke. "It was a nova."
Melina shrugged. "Why not? We put a skull and crossbones to indicate poison. We don't mean it literally. It's figurative."
"They don't know figurative. They're a literal species, maybe because of the way they come genetically preprogrammed, like ants. To them, something either is or it isn't, or it is ignored. It can't be partway, unless it's something under construction. So when they use a nova symbol--"
Now the horror came to her face too. "You mean--?"
"I mean that when they say nova, they mean nova! If we abuse the reactor--"
"Our sun will go nova," she said.
"It must be keyed in. The moment the reactor starts to go wrong, it sends the destruct signal to the sun. The sun flares up and takes everything out, maybe through the orbit of Jupiter. Just a little flare, on the galactic scale, but our species will be gone. Just as those other species went, thousands of years ago when they didn't pass the test, and now we're seeing their novas. There are three requirements, one being that we achieve limited space travel on our own, another that we are able to recognize the nature of the artifact, and the third is undefined--but now we know that it means to do it right, or else."
"No second chance," she agreed, staring straight ahead.
"We're shooting for all the marbles!" His face felt frozen. He remembered the dream he had had, of mankind ending. No dream, but an alien warning!
"All the marbles," she echoed hollowly. "God, Doug--"
"Yeah." He arrowed on down the passage, feeling numb.
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
An alien LHC turned on... and gone!
can someone pass me the SPF9000000000+ sunscreen please.