- A death ray from space may have caused one of the Earth's
worst mass extinctions 443 million years ago, it has been claimed. Scientists
believe the pattern of trilobite extinctions matched the effects of a nearby
gamma-ray burst.
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- Gamma-ray bursts are the most powerful cosmological explosions
known. As giant stars collapse into black holes at the end of their lives,
they shoot out intense pulses of gamma rays. Adrian Melott, of the University
of Kansas, says such a burst within our galaxy could produce enough nitrogen
dioxide to blot out half the sunlight reaching the Earth.
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- ©2003 Scotsman.com
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- http://www.thescotsman.co.uk/scitech.cfm?id=1062392003
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