The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
Simon Warwick-Smith
Posted on 12/30/2003 2:29:48 PM PST by EUPHORIC
Scientists have new theory on ice age
KU researchers believe gamma-ray burst caused extinctions, cooling
By Alea Smith - Special to the Journal-World
Monday, December 29, 2003
Researchers now believe a cosmic explosion 440 million years ago may have decimated life on Earth.
Kansas University scientists are attracting international attention with their research into the possibility a massive gamma ray explosion caused an ice age that wiped out much of the life on Earth.
"It appears that the (gamma ray) bursts are a serious danger, although not something you would expect to hit us very often, maybe every few hundred million years," said Adrian Melott, a professor of physics and astronomy.
Melott and Bruce Lieberman, an associate professor of geology, are studying whether gamma ray bursts were responsible for high extinction rates in shallow-water marine species -- amoebas, sponges and coral-like creatures and some marine species with hard shells -- while other species survived.
The effects were worse on shallow-water species, the scientists believe, because deeper water protected other species.
"There is a variety of evidence for this particular time period," Lieberman said. "There is chemical evidence as well as the animals that made it through and those that go extinct."
Two international science magazines, New Scientist and Nature, have recently reported the KU researchers' hypothesis.
Others working on the theory since last spring have included Claude Laird, associate professor of physics and astronomy at KU; Mikhail Medvedev, assistant professor of physics and astronomy at KU; and officials from the NASA Goddard Space Flight Center in Greenbelt, Md.
Previous theories have attributed the extinction to the start of an ice age but offer no explanation as to what triggered the ice age during a relatively warm climate.
Gamma-ray bursts occur when a giant star explodes, creating a burst of nuclear energy in the form of gamma-rays, which have the smallest wavelength and most energy of all radiation.
The Earth's atmosphere would absorb the energy, which would separate nitrogen and oxygen molecules in the atmosphere, creating nitrogen oxides, including nitrogen dioxide, which plays a major role in the atmospheric reactions that produce ground-level ozone or smog.
The scientists' research has led them to believe the long-term effects of gamma-ray bursts would deplete the ozone and cause global cooling and acid rain. It would also increase the amount of direct ultraviolet rays from the sun, which only reach a depth of 10 meters in water. This explains why only shallow marine species were involved in the extinction.
The trilobite, an extinct hard-shelled marine creature, has been the focus of research so far. Its extinction pattern in the fossil record is similar to what scientists would expect to find with gamma-ray bursts. They are now looking further into other species that survived and died out during this time to find more connections.
Astronomers have observed and recorded many recent gamma-ray bursts from distant galaxies that have been harmless to the Earth.
"These bursts occurred more often when the solar system first formed," Lieberman said. "Ones like we think caused this extinction occur once every billion years or so, but that's just an estimate."
Melott said if a gamma-ray burst occurred within 10,000 light years on this side of the galaxy, the effects on Earth would be devastating.
"Anyone outside when this occurred would be blinded," Melott said. "The effects would be noticed right away."
The content of science is the world and how it works. This is "significant." We can't imagine all the uses of such knowledge in advance, but it's something I can't understand not wanting. (Unless it's hard, of course.)
I think you're comparing apples and oranges, somehow.
That thing may have already popped, and at 8000ly away, the gamma shower could have been on it's way to us for the last few thousand years.
Pions are sub-atomic particles formed from the decay of a (particle known as a) kaon. (particle physics)"
you forgot one:
Peons are BraBra Streisand's litte people who put rose petals in her toilet water.
That thing may have already popped, and at 8000ly away, the gamma shower could have been on it's way to us for the last few thousand years.
As unstable as it appears, I'd be surprised if it lasted another 8,000 years (beyond where it was 8,000 years ago). IOW, the trigger has been pulled, and the bullet is on its way. The only question is when it'll hit.
[...science know absolutely nothing about what causes anything.]
I'm guessing you put all of your faith in shamans and witch doctors, then. :^)
2 years for a reply?! Are you a little behind on FR?
Seriously, I was being a bit sarcastic even though there is an element of truth hidden in my statement.
The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
Simon Warwick-Smith
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