APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Gamma-Ray Burst: A Milestone Explosion
Explanation: Gamma-Ray Bursts (GRBs) were discovered by accident. Thirty three years ago today, satellites first recorded a GRB . The data plotted here show that the count rate of the satellite gamma-ray instrument abruptly jumped indicating a sudden flash of gamma-rays. The Vela satellites that detected this and other GRBs were developed to test technology to monitor nuclear test ban treaties . With on board sensors they watched for brief x-ray and gamma-ray flashes, the telltale signatures of nuclear explosions. As intended, the Velas found flashes of gamma-rays - but not from nuclear detonations near Earth. Instead, the flashes were determined to come from deep space! Dubbed “cosmic gamma-ray bursts” they are now known to be the most powerful explosions originating in distant galaxies. What could power a gamma-ray burst ?
| Date | July 2, 2000 |
|---|---|
| Credit | Credit: R. Klebesadel, I. Strong & R. Olson ( LANL ), Vela Project |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |