Death of massive star creates brightest burst ever seen
March 20th, 2008
The extremely luminous afterglow of GRB 080319B was imaged by Swift's X-ray Telescope (left) and Optical/Ultraviolet Telescope (right). This was by far the brightest gamma-ray burst afterglow ever seen. Credit: NASA/Swift/Stefan Immler, et al.
Gamma-Ray Bursts are the most powerful explosive events in the Universe. They occur in far-off galaxies and so are usually faint. But on the morning of March 19th 2008 the Swift satellite found a burst which was so bright it could have been seen without binoculars or a telescope even though it was seven thousand times further away than the Andromeda galaxy.
The burst was discovered by the Swift satellite on a fantastic day for GRB hunters. Swift typically finds only two a week; but for the first time Swift found five bursts within 24 hours. The second burst of the day is the new record holder. The enormous energy released in the explosion – brighter than the light from all of the stars in five million Milky Way Galaxies – was caused by the death of a massive star which collapsed to form a black hole.
Dr. Julian Osborne of the University of Leicester, lead investigator for the Swift UK Science Data Centre, said “It’s great to find so many GRBs in one day, and the discovery of the brightest burst ever seen will allow us to explore this incredible explosion in exquisite detail.”
The location of the burst was rapidly pinpointed using the UK-built X-ray and Optical cameras on Swift. Dr. Paul O’Brien, also of the University of Leicester and a member of the Swift Science Team said, “The explosion happened at a distance of over twenty billion light years from Earth. To detect a naked eye object from such a distance really is extraordinary.”
Astronomers around the world are now observing the decaying glow from this burst as it fades away. These include UK teams from the Universities of Leicester, Warwick and Hertfordshire using the Gemini-North Telescope in Hawaii and the Liverpool John Moores University using the Liverpool Telescope on La Palma in the Canary Islands.
Professor Nial Tanvir, of the University of Leicester, said: “Our Gemini observations allowed us to measure the distance to the GRB, and to investigate the behaviour of gas close to the burst as it was blasted by the energy of the explosion”.
Source: University of Leicester
Jun 08, 2009 |
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"it was seven thousand times further away than the Andromeda galaxy." (2.5 million * 7,000 = 17.5 billion)
So is it 20 Billion or 17.5 billion?
I thought the current estimated age of the universe is 13.7 billion years so how could it be either?
If this GRB is shown to be older than the current estimated age of the universe, is that not an important news story in itself?
The gist of the explaination is this: Two galaxies are near to each other when the universe is only 1 billion years old. The first galaxy emits a pulse of light. The second galaxy does not receive the pulse until the universe is 14 billion years old. By this time, the galaxies are separated by about 26 billion light years; the pulse of light has been traveling for 13 billion years; and the view the people receive in the second galaxy is an image of the first galaxy when it was only 1 billion years old and when it was only about 2 billion light years away.
(please don't say on the morning of March 19th 2008 - lol)
good question
1) Original distance between two points when the photon was emitted
2) Current distance between two points as if the universe could be seen from a global frame of reference (that seems what they are using in the article)
3) Current distance between two points as a percentage of the current light radius of the visible universe (13.7 billion light years).
Number 3 is what is normally used, but either of the other two can be used if you are in the mood for funkiness.
http://www.nasa.g...GRB.html
If the theories are correct, then the moment of gamma burst arrival should be quite significantly delayed towards the flash in the visible range.
back in that time, I guess such massive stars were much more common than today... maybe the inhabitants of that galaxy are TODAY watching powerful gamma ray bursts from stars in the Milky Way galaxy... stars that exploded (or imploded) even before the Sun existed. Since the light of such explosions passed by the Sun 7.5 billion years ago, we will never know about them. But aliens living at vast distances will see the Milky Way past.