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Астронет: Астрономическая картинка дня Вспышки гамма-излучения http://www.astronet.ru/db/msg/1166656/eng |
Credit & Copyright: R. Klebesadel, I. Strong & R. Olson
(LANL),
Vela Project
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?
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.