A Hubble Space Telescope image of the galaxy that was the source of Gamma-Ray Burst 971214.

Once considered clockwork-like and orderly, new findings are revealing the universe's chaotic and violent history.

Edward Hubble shattered the idea of a fixed universe in the 1920s when he discovered countless galaxies flying away from each other. Hubble's research led to the theory of the Big Bang, the cataclysmic event that started the universe some 15 billion years ago.

Now a team has found evidence of an explosion, labeled GRB (gamma-ray burst) 971214, with an intensity second only to the Big Bang. The team used NASA's Hubble Space Telescope and a host of satellites and was led by Professors Shrinivas Kulkarni and George Djorgovski of the California Institute of Technology.

The team's data, published in the May 7th edition of Nature, suggests that the explosion happened 12 billion light-years from Earth. They estimate that the explosion had an impact several times greater than an exploding star, or supernova -- the most powerful observed phenomenon before the GRB 971214 discovery.

An image of the visible-light afterglow of the GRB 971214 burst, obtained with the W.M. Keck 10-meter telescope on Mauna Kea, Hawaii, indicated by the yellow arrow.

"For the the 10 seconds this was shining in gamma-rays, it was 5 billion times brighter than a supernova," Prof. David Helfand, an astronomy professor at Columbia University, told Phil Ponce on the NewsHour.

And even though it outshined all the stars in the universe for a brief moment, Prof. Helfand emphasized that GRB 971214 is not directly related to the Big Bang.

What caused GRB 971214? Will other explosions be found? How unstable and choatic is our universe? Will GRB 971214's discovery change the way we view the universe?

Your questions about GRB 971214 are answered by Dr. Helfand.

Questions asked in this forum:

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	How do we know that the explosion occurred 12 billion light-years away?
	Could a gamma-ray burst occur in our galaxy?
	What are the leading theories explaining GRB 971214?
	What does the gamma-ray blast tell us about the early universe?
	What is the Big Bang?