Gamma Ray Bursts Blamed For Mass Extinctions

www.newscientist.com...


This is quite a startling revelation if it can be proven, although the theory has its skeptics already. However the scenario presented would fit with what is known. I am not sure if the specific mass extinction events that are referred to in the article are already blamed on asteroid/ large meteorite impacts. If you ask me its just one more thing to worry about.

All the bursts astronomers have recorded so far have come from distant galaxies and been harmless on the ground, but if one occurred within our galaxy and was aimed straight at us, the effects could be devastating, according to astrophysicist Adrian Melott of the University of Kansas in Lawrence.

The Earth's atmosphere would soak up most of the gamma rays, Melott says, but their energy would rip apart nitrogen and oxygen molecules, creating a witch's brew of nitrogen oxides, especially the toxic brown gas nitrogen dioxide that colours photochemical smog (see graphic).

Melott estimates that a burst would produce enough of the gas to darken the sky, blotting out half the visible sunlight reaching the Earth. Nitrogen dioxide would also destroy the ozone layer, exposing surface life to a dangerous overdose of ultraviolet radiation from the sun for a year or more until the ozone recovered.

To me it is no less plausible than gamma irradiation creating the behemoth called the Incredible Hulk out of the puny Bruce (or David) Banner.

"Bah! Puny gamma rays will not harm Hulk! Hulk will SMASH puny gamma rays!

-- Sniff -- Puny gamma rays have killed ALL puny humans. Bah! Now Hulk has only puny insects for company.

It is time for Hulk to walk... and find Hulk's place in the SUN."

[Edited on 25-9-2003 by MaskedAvatar]

The effects described are no doubt perfectly plausible, but the author ignores a problem that has to be answered with this theory... where did the GRB come from?

Normally, the kind of star the author is referring to is called an X Ray star, would be rather easy to spot, even the remnants from 400+ million years previously. However, to my knowledge at least, no such exist within our galaxy.

I read it on the Yahoo news... unexplain gamma bursts. Scientists are trying to build satelites to find the source(s) of them.

Here ya go MA:





And DR....the 'GRB' came from:







Seriously though....maybe the article can help answer or possibly pose further questions:

"Cosmological Gamma-Ray Bursts and Hypernovae Conclusively Linked"
Link:
www.spacedaily.com...


regards
seekerof