What are Gamma Bursts and where do they come from???

Answer 1

Gamma-ray bursts are short-lived bursts of gamma-ray photons, the most energetic form of light. At least some of them are associated with a special type of supernovae, the explosions marking the deaths of especially massive stars.

Lasting anywhere from a few milliseconds to several minutes, gamma-ray bursts (GRBs) shine hundreds of times brighter than a typical supernova and about a million trillion times as bright as the Sun, making them briefly the brightest source of cosmic gamma-ray photons in the observable Universe. GRBs are detected roughly once per day from wholly random directions of the sky.

Until recently, GRBs were arguably the biggest mystery in high-energy astronomy. They were discovered serendipitously in the late 1960s by U.S. military satellites which were on the look out for Soviet nuclear testing in violation of the atmospheric nuclear test ban treaty. These satellites carried gamma ray detectors since a nuclear explosion produces gamma rays. As recently as the early 1990s, astronomers didn't even know if GRBs originated at the edge of our solar system, in our Milky Way Galaxy or incredibly far away near the edge of the observable Universe. (That is, they didn't know how far away GRBs were to within a factor of a few billion light years!) But now a slew of satellite observations, follow-up ground-based observations, and theoretical work have allowed astronomers to link GRBs to supernovae in distant galaxies.

Answer 2

Are caused by supernovae explosions of stars about 50 times the size of our sun. The explosions generate black holes. Incidentally they have just observed light & infrared coming from the star at the same time as the gamma ray burst. (for the first time). That star located was nearby to our galaxy.
Dan.

Answer 3

You will get all about it on :
http://imagine.gsfc.nasa.gov/docs/science/know_l1/bursts.html

Answer 4

you may need to take a look at http://www.raybanchina.net