Gamma Ray Burst Visible At Record Distance
Invisible Pink Unicorn writes "A gamma ray burst detected on March 19 by NASA's Swift satellite has set a new record for the most distant object that could be seen with the naked eye. The burst had a measured redshift of 0.94, meaning the explosion took place 7.5 billion years ago. The optical afterglow from heated gas was 2.5 million times more luminous than the most luminous supernova ever recorded, making it the most intrinsically bright object ever observed by humans in the universe. The previous most distant object visible to the naked eye is the nearby galaxy M33, a relatively short 2.9 million light years from Earth."
If I read correctly, a GRB of this magnitude occurring 2700 light years away would be as bright as the sun. Ouch.
"Be light, stinging, insolent and melancholy"
Ready GO!
so long as it isn't 100-900 light years away, the earth wouldn't be destroyed. still, it is going to be in the night sky for at least a few months
If people can get past, can they get future? Best way to confuse a stoner
I don't know...looks photoshopped to me.
Absolute power corrupts absolutely. indymedia
Ze goggles!!! Zey do nothing!!!!!!!!!!
(kisses karma goodbye)
Or perhaps it concentrated its energy in a narrow jet that was aimed directly at Earth. They're shooting at us!
Anyway, it's a good thing that this occurred so far away, instead of nearby. There are a few hypergiant stars known to exist in our galaxy like Eta Carinae and the Pistol Star which are inherently unstable. And in 2004 a GRB was emitted by a magnetar half way across the galaxy that, were it visible, would have been brighter than a full moon. Its been proposed that GRB's may be a factor in past extinction events here on earth.
For you newcomers, a record was like a mechanical CD but larger. The diameter of a CD is about half that of a Long Playing Record, so "Record Distance" is a distance comparable to the width of two CDs. I don't know why astronomers are the ones studying lights at that distance.
The burst had a measured redshift of 0.94
Could someone smarter at astrophysiky stuff please help us noobs understand that?
I understand that redshift is like the doppler effect, only for light, and red means it's moving away from you and blue means it's moving toward you, but how do you compute absolute values for it? How do you tell the difference between a redshifted flash of light and a stationary light that is red to begin with?
Thanks
Heh... appropriately enough, my "please type the word in this image" word is "crimson".
From the article:
> Later that evening, the Very Large Telescope in Chile and the Hobby-Eberly Telescope in Texas measured the burst's redshift at 0.94. A redshift is a measure of the distance to an object. A redshift of 0.94 translates into a distance of 7.5 billion light years, meaning the explosion took place 7.5 billion years ago, a time when the universe was less than half its current age and Earth had yet to form. This is more than halfway across the visible universe
This contains some serious misunderstandings. Just because it's at a distance of 7.5 billion light years away, that doesn't mean it happened 7.5 billion years ago because the universe has expanded since then. We have seen objects that are more than 50 billion light years away, but the universe is only 13 billion years old.
Also this object is nowhere near 'halfway across the visible universe'. The visible universe is 46 billion light years in radius (with us at the centre).
Gamma ray bursts emit a *lot* of light at longer wavelengths than gammas. Actually, they spend more time emitting longer-wave light than they do emitting gammas. The gamma pulse is very brief, but the other forms of radiation last a lot longer.
Just re-member that you're standing on a planet that's evolving and revolving at nine-hundred miles an hour.
That's orbiting at nineteen miles a second, so it's reckoned, a Sun that is the source of all our power.
The Sun and you and me and all the stars that we can see, are moving at a million miles a day, In an outer-spiral arm at forty-thousand miles an hour, of the Galaxy we call the Milky Way.
Our galaxy itself contains a hundred-billion stars, it's a hundred thousand lightyears side to side.
It bulges in the middle, sixteen-thousand lightyears thick, but out by us it's just three-thousand lightyears wide.
We're thirty thousand lightyears from Galactic central point, we go round every two-hundred-million years.
And our Galaxy is only one of millions of billion in this amazing and expanding Universe The Universe itself keeps on expanding and expanding in all of the directions it can whizz. As fast as it can go, the speed of light you know, twelve-million miles a minute and that's the fastest speed there is.
So remember when you're feeling very small and insecure how amazing unlikely is your birth. And pray that there's intelligent life somewhere out in space, 'cos there's buger all down here on Earth!
Ask not what you can do for your country. Ask what your country did to you
If I read correctly, a GRB of this magnitude occurring 2700 light years away would be as bright as the sun. Ouch.
Ouch indeed. (I'm sure somebody will check your math and adjust the distance if necessary. So let's go with the premise of a solar input's worth from nearby.)
At that sort of distance the red shift would be virtually nonexistent. A kilowatt per square meter of gamma rays would make you toasty warm all the way through, not just on the skin.
Also: Goodbye DNA and RNA. Presuming you're still alive (for some value of alive) after the flash you'd be running on the proteins you've already got for your last few days. Then the deep ocean and rift vent critters get their chance. (Presuming, of course, that an associated neutrino flux didn't get them and the planet has to start from scratch.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
You do not believe me? Have you ever read The Star? Yes, it is but a silly fantasy of mine, yet I shall paraphrase it nevertheless: "Oh Universe, there were so many stars in the Milky Way you could have used. What was the need to put a whole distant galaxy (with civilizations, perhaps) to the fire, that this giant fireworks (admittedly much more breathtaking than a mundane supernova) might honour the great writer having just passed away?"
Ezekiel 23:20
Serpentine! Serpentine!
"And THIS is the galaxy he lived in!..."
*maniacal laughter*
With the first link, the chain is forged.