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Posted on 03/05/2008 1:07:09 PM PST by Squidpup
It has already exploded and the gamma ray burst will reach Earth on Dec 21, 2012.
From Wikipedia:
Research has been conducted to investigate the consequences of Earth being hit by a beam of gamma rays from a nearby (about 500 light years) gamma ray burst. This is motivated by the efforts to explain mass extinctions on Earth and estimate the probability of extraterrestrial life. A gamma ray burst at 6000 light years would result in mass extinction; a 1000 light year distant burst would be equivalent to a 100,000 megaton nuclear explosion — like standing a couple miles from Hiroshima everywhere on earth. A burst 100 light years away would blow away the atmosphere, create tidal waves, and start to melt the surface of the earth. There is a one in a million chance that there could be a gamma ray burst as near as the earth’s closest star, Alpha Centauri, in the lifetime of the earth. Such a burst, at 4.3 lightyears distant, would effectively incinerate the earth[32].
A consensus seems to have been arrived at the fact that damage by a gamma ray burst would be very limited because of its very short duration, and the fact that it would only cover half the Earth, the other half being in its shadow. A sufficiently close gamma ray burst would however, result in serious damage to the atmosphere, shutting down communications (due to electro-magnetic disturbances), perhaps instantly wiping out half the ozone layer, and causing nitrogen-oxygen recombination, thereby generating acidic nitrogen oxides. These effects could diffuse across to the other side of the Earth, severely diminish the global food supply, and result in long-term climate and atmospheric changes and a mass extinction, reducing the global population to perhaps 10% of what it can now support. However, the damage from a gamma ray burst would probably be significantly greater than a supernova at the same distance.
The idea that a nearby gamma-ray burst could significantly affect the Earth’s atmosphere and potentially cause severe damage to the biosphere was introduced in 1995 by physicist Stephen Thorsett, then at Princeton University.[33] In 2005, Scientists at NASA and the University of Kansas released a more detailed study which suggested that the Ordovician-Silurian extinction events which occurred 450 million years ago could have been triggered by a gamma-ray burst. The scientists do not have direct evidence to suggest that such a burst resulted in the ancient extinction, rather the strength of their work is their atmospheric modeling, essentially a “what if” scenario. The scientists calculated that gamma-ray radiation from a relatively nearby star explosion, hitting the Earth for only ten seconds, could deplete up to half of the atmosphere’s protective ozone layer, the recovery for which would take at least five years. With the ozone layer damaged, ultraviolet radiation from the Sun would kill much of the life on land and near the surface of oceans and lakes, disrupting the food chain. While gamma-ray bursts in our Milky Way galaxy are indeed rare, NASA scientists estimate that at least one nearby event has probably hit the Earth in the past billion years. Life on Earth is at least 3.5 billion years old. Dr. Bruce Lieberman, a paleontologist at the University of Kansas, originated the idea that a gamma-ray burst specifically could have caused the great Ordovician extinction. He said, “We do not know exactly when one came, but we’re rather sure it did come - and left its mark. What’s most surprising is that just a 10-second burst can cause years of devastating ozone damage.”[34]
Comparative work in 2006 on galaxies in which GRBs have occurred suggests that metal-deficient galaxies are the most likely candidates. The likelihood of the metal-rich Milky Way galaxy hosting a GRB was estimated at less than 0.15%, significantly reducing the likelihood that a burst had caused mass extinction events on Earth.[35]
The Wolf-Rayet star WR 104, located 8000 light years from Earth, has been found to have a rotational axis aligned within 16° of the planet. The chances of it producing a gamma ray burst are small but if it did it would be close enough to have a significant impact on Earth.[36]
Ok, Cubs fans, you’ve only got five more seasons of futility to go through.
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How much do you have to "lead" a planet when shooting at it from 8,000 light years away?
>>of course, if we aren’t on the axis, even by just a little [undetectable] bit, we could be far enough out of the path to not even be able to measure its effect.
Exactly. Even one arcsecond off the axis from 8,000 light-years away translates to a miss by [counting on fingers] about 366,000,000,000 kilometers. People sometimes forget just how big the universe is.
No way. This is the year man! And Jr is gonna win the cup!
And how is this relevant to the question of classifying Pluto?
Faster than a speeding bullet.
Scientists see what they want to see. Anything that scares people will get into the news, and give the scientist publicity so he/she can get more grants from the government.
Thanks for a good laugh!
Brilliant!
“In any case there isn’t anything we can do anyway.”
We could build this fence. We’ll have the materials the U.S. government has accumulated for the fence they aren’t going to build between the U.S. and Mexico.
Women and minorities will be the hardest hit.
If the Big Bang theory was correct, wouldn’t stars in the same astronomical neighborhood be about the same age?
The Pluto debate had little to do with science. It was a debate about scientists egos.
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