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Apophis May Destroy West Coast

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I just saw on C-SPAN Book TV astrophysicist Neil deGrasse Tyson state that an asteroid the size of the Rose Bowl was discovered in 2004. The asteroid will pass closer to earth than the communication satellites that orbit us in 2029. The asteroid will pass over Europe. He stated should the asteroid pass within a specific window (there is some error within the current calculation), the gravity of earth will cause the asteroid to return to earth seven years later and stike the earth in the Pacific Ocean off the coast of Southern California. THIS IS NOT A JOKE!! The entire west coast of California will be destroyed by a fifty foot tsunami that will cycle back and forth approximately 20+ times. You people out there better move now.

'Nova' asteroid could rock your world in '36

It wasn't quite Chicken Little warning that the sky was falling, but astrophysicist and PBS "Origins" star Neil deGrasse Tyson yesterday warned TV writers that an asteroid is coming - very, very close to Earth.

A projected trajectory shows the asteroid, Apophis (named for the Egyptian god of death and darkness), will come very close to our planet in 2029, and have a chance of hitting Earth on its next pass in 2036.

If it hits, the impact would equal the force of 100 nuclear bombs, said Tyson, the new host of "Nova scienceNOW." The show will devote a segment of its Oct. 3 season premiere to "doomsday asteroids."

Tyson says we have plenty of time to act, react and reassess. "In 2029," Tyson said, "on Friday the 13th in April, Apophis is a certainty to come closer to Earth than our communications satellites. It'll be the largest thing to come that close in recorded history ... and depending on that trajectory, will determine whether it will hit us seven years later."

Apollo 9 astronaut Russell L. Schweickart, an advocate of organizing to prepare for such threats, said new data put the odds of a strike at 1 in 38,000. That's still enough, he said, to take the situation seriously.

Is there good news in this asteroid doomsday scenario? Yes and no. "Apophis, if it hits, will not contribute to global warning," Tyson predicted. "It'll just wipe out the entire West Coast of North America."

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This is suggestive of similar scares I've heard about in the past, and I am particularly skeptical when its reported on PBS.

Taking the matter at face value, this is an opportunity to consider the recent debate over the meaning of the "possible" in a concrete case.

Is 1:38000 considered "possible" when the consequence of the event is as signficant as the destruction of the US West Coast (all joking aside)?

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Is a killer tsunami that takes out the west coast all that would happen? I'm not trying to be funny. What little I know is what I've seen on History Channel doomsday shows, but it seems that a rock that big would cause a global catastrophe.

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Is a killer tsunami that takes out the west coast all that would happen? I'm not trying to be funny. What little I know is what I've seen on History Channel doomsday shows, but it seems that a rock that big would cause a global catastrophe.

That's all he talked about during the brief discussion of the issue. From what was said during the TV show, the rock will land in the water. Also, he said that the rock is travelling at 15 miles per hour relative to the earth. That may have something to do with the amount of energy released. I'm sure the damage would be well beyond California, all along the Americas and affecting Asia and Australia.

Tyson, mentioned an interesting side issue. If the rock simply crashes into the earth, then insurance companies wouldn't have to pay since it's an "act of god." However, he said that there are plans underway to try and divert the asteroid should it pass within the window that would cause it to swing back and hit earth. He wondered if we moved the asteroid sufficiently to avoid California, but it landed in New York or Europe or other populated area, could the people who moved the asteroid be sued? Would insurance companies be required to pay since the catstrophe was influenced by man's actions?

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That's all he talked about during the brief discussion of the issue. From what was said during the TV show, the rock will land in the water. Also, he said that the rock is travelling at 15 miles per hour relative to the earth. That may have something to do with the amount of energy released. I'm sure the damage would be well beyond California, all along the Americas and affecting Asia and Australia.

Tyson, mentioned an interesting side issue. If the rock simply crashes into the earth, then insurance companies wouldn't have to pay since it's an "act of god." However, he said that there are plans underway to try and divert the asteroid should it pass within the window that would cause it to swing back and hit earth. He wondered if we moved the asteroid sufficiently to avoid California, but it landed in New York or Europe or other populated area, could the people who moved the asteroid be sued? Would insurance companies be required to pay since the catstrophe was influenced by man's actions?

If calculations show it is heading for Mecca, I may have to revise my metaphysics. :):)

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I haven't seen a big splash about this in the science news, so maybe the calculatiions aren't as good as this guy says they are. But if Apophis IS a threat, I guess we'd finally have a use for all those nuclear weapons that have been stockpiled for the last fifty-plus years. I know there's been talk for decades about what to do if Earth is ever threatened by an asteroid, and there were two movies based on the idea a few years ago. No doubt war-gamers as well as scientists have been working on scenarios.

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I haven't seen a big splash about this in the science news, so maybe the calculatiions aren't as good as this guy says they are. But if Apophis IS a threat, I guess we'd finally have a use for all those nuclear weapons that have been stockpiled for the last fifty-plus years. I know there's been talk for decades about what to do if Earth is ever threatened by an asteroid, and there were two movies based on the idea a few years ago. No doubt war-gamers as well as scientists have been working on scenarios.

If memory serves, the 1 in 38,000 probability of collision is based on sparse observational data gathered over a small section of a highly elliptical orbit. As a result, tiny measurement errors propagate into enormous errors in future predictions of position and velocity. Astronomers interested in this problem are scrambling for more data to refine their estimates of the future probability of collision.

Should additional data result in a conclusion that Apophis is a real risk, then the solution will be to either slow it down or speed it up ever slow slightly many years before the expected collision. The slightest intrack velocity change early on will result in a great future payoff in causing it to reach earth's orbit either early or late. While blowing it up with nuclear weapons makes for great Hollywood fare, it is arguably more dangerous than leaving it intact. Pick your poison: would you rather get hit by a .45 slug or 12 guage buckshot?

In any event, a colleague of mine has been working on this problem lately, and in the next few weeks he is headed to a conference in Washington to discuss Apophis and other matters related to "planetary defense" -- the buzzwords used by people concerned with asteroid/comet collisions. I'll be sure to pick his brains and report back.

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If memory serves, the 1 in 38,000 probability of collision is based on sparse observational data gathered over a small section of a highly elliptical orbit. As a result, tiny measurement errors propagate into enormous errors in future predictions of position and velocity. Astronomers interested in this problem are scrambling for more data to refine their estimates of the future probability of collision.

Should additional data result in a conclusion that Apophis is a real risk, then the solution will be to either slow it down or speed it up ever slow slightly many years before the expected collision. The slightest intrack velocity change early on will result in a great future payoff in causing it to reach earth's orbit either early or late. While blowing it up with nuclear weapons makes for great Hollywood fare, it is arguably more dangerous than leaving it intact. Pick your poison: would you rather get hit by a .45 slug or 12 guage buckshot?

In any event, a colleague of mine has been working on this problem lately, and in the next few weeks he is headed to a conference in Washington to discuss Apophis and other matters related to "planetary defense" -- the buzzwords used by people concerned with asteroid/comet collisions. I'll be sure to pick his brains and report back.

Those odds are for the possibility of the asteroid crashing into the earth after the first pass. It is known that the asteroid will pass within the orbit of current communications statellites. That's too close for my comfort, but I'm sure it will make for a lot of doomsday predictions by the crazies.

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If calculations show it is heading for Mecca, I may have to revise my metaphysics. :):)

We must pray.

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From what was said during the TV show, the rock will land in the water. Also, he said that the rock is travelling at 15 miles per hour relative to the earth.

I have no idea what he could have meant by that. It is estimated that, should Apophis actually strike the Earth, it would enter the atmosphere at approximately 28,000 mph.

If memory serves, the 1 in 38,000 probability of collision is based on sparse observational data gathered over a small section of a highly elliptical orbit.

NASA's current NEO (Near Earth Objects) estimate puts the probability at a 1 in 45,000 chance of impacting Earth, with a significant sigma of -2.43 as a measure of the confidence in impact orbit with the observational data. I'm not packing my bags to leave California quite yet. :)

In any event, a colleague of mine has been working on this problem lately, and in the next few weeks he is headed to a conference in Washington to discuss Apophis and other matters related to "planetary defense" -- the buzzwords used by people concerned with asteroid/comet collisions. I'll be sure to pick his brains and report back.

Yes, that's the March 5th Planetary Defense Conference. Is your colleague presenting a paper on Apophis? If so, I'd certainly be interested in whatever you glean from talking to him about it. The threat has been downgraded so much since it was identified in 2004 that I am perplexed at all the flurry and interest right now. I read a couple of papers a year or two ago, and it seemed that if the threat was real by the late 2020s there would be time to launch a craft whose very presence should be sufficient to gravitationally deflect Apophis' path from the Earth.

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NASA's current NEO (Near Earth Objects) estimate puts the probability at a 1 in 45,000 chance of impacting Earth, with a significant sigma of -2.43 as a measure of the confidence in impact orbit with the observational data. I'm not packing my bags to leave California quite yet. :)

Good point. I had also read the NASA number, and I don't know where the new one came from. Point taken, though. My biggest threat to continued living in Southern California is the cost of living/housing. But that is a matter for another thread. And in the meantime, I will bask in the March sun while my colleague suffers through frigid weather back east. Insert obligatory global warming quip here.

Yes, that's the March 5th Planetary Defense Conference. Is your colleague presenting a paper on Apophis? If so, I'd certainly be interested in whatever you glean from talking to him about it. The threat has been downgraded so much since it was identified in 2004 that I am perplexed at all the flurry and interest right now. I read a couple of papers a year or two ago, and it seemed that if the threat was real by the late 2020s there would be time to launch a craft whose very presence should be sufficient to gravitationally deflect Apophis' path from the Earth.

Rusty Schweikart prefers the gravity tractor approach. My colleague prefers using a heavy impactor probe like the one used by the Deep Impact mission to achieve the same effect. I asked my colleague about the gravity tractor, and he confessed that he did not fully understand it. But I suspect that he -- and I -- will soon.

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He wondered if we moved the asteroid sufficiently to avoid California, but it landed in New York or Europe [...]

The "black rock" of Mecca might be a meteorite discovered long ago. I'm all for giving them another, far larger, one, delivered C.O.D. to their front doorstep.

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IWhile blowing it up with nuclear weapons makes for great Hollywood fare, it is arguably more dangerous than leaving it intact. Pick your poison: would you rather get hit by a .45 slug or 12 guage buckshot?

I wasn't thinking of actually "blowing it up" with nuclear weapons. But if Apophis is pretty big and pretty solid (unlike a comet head), I'd think that nuclear weapons set off on just one side might be the easiest way to divert it. If this COULD be done, it would be easier than building a huge space tug.

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The "black rock" of Mecca might be a meteorite discovered long ago. I'm all for giving them another, far larger, one, delivered C.O.D. to their front doorstep.

Let's get serious. If a major asteroid hit Mecca, the collatrral damage might well take out Israel and India, among others. And that's not even counting the effects of dust clouds, which could put the whole planet in the deep freeze.

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I wasn't thinking of actually "blowing it up" with nuclear weapons. But if Apophis is pretty big and pretty solid (unlike a comet head), I'd think that nuclear weapons set off on just one side might be the easiest way to divert it. If this COULD be done, it would be easier than building a huge space tug.

As I understand it, you wouldn't need a hugh spaceship, just a ship with hugh thrusters that would force the asteroid to change direction ever so slightly. The earlier the better.

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Let's get serious. If a major asteroid hit Mecca, the collatrral damage might well take out Israel and India, among others. And that's not even counting the effects of dust clouds, which could put the whole planet in the deep freeze.

Of course. It was partly a joke. Something the size of the nickel-iron rock (perhaps 150 feet across) that created the famous Barringer crater in Arizona would be about right though...

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Is there any chane the asteroid would move the earth's orbit further from the sun so that global warming would be counterbalanced? Maybe some global cooling?

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My understanding on that gravity tug idea is that mass exerts a gravitational force. Simply sticking the gravity tractor near it, would cause both the tractor to be attracted to the asteroid and the asteroid to be attracted to the tractor. Doing that soon enough and even the tiniest angle change that doing that would cause, would be enough to stop it hitting the Earth.

Think of it like a tiny magnet, pulling an absolutely giant magnet, ever so slightly towards it.

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Paul's Here wrote:

<<Is there any chance the asteroid would move the earth's orbit further from the sun so that global warming would be counterbalanced? Maybe some global cooling?>>

Not a chance. Asteroids have really TINY masses. You might as well try to move a battleship by throwing a baseball at it. There has been speculation about moving planets since Olaf Stapledon's STAR MAKER (1937). Larry Niven's A WORLD OUT OF TIME imagined a distant future in which Earth has been moved to orbit Jupiter because the Sun was turned inti a red giant -- and he gets into some of the details about how that MIGHT be accomplished. Trust me, it wouldn't be easy. And there are better, cheaper ways to deal with counteract any global warming.

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Here's an "official" JPL website summarizing the potential threat from Apophis.

A notable figure of the energy release is their estimate of 400 MT (megatons of TNT). The largest thermonuclear bomb ever detonated was by Russia in 1961 (see http://www.answers.com/topic/tsar-bomba) with a yield of 50 MT. So, Apophis would only be 8 times that size. The energy released by the great Indian Ocean quake of 2004 was estimated at 800 MT, so an Apophis strike would represent half that amount of energy (though in a concentrated point all at once, rather than spread out over 1600 kilometers over 10 minutes.)

Where it hits, of course, would be significant, e.g. in the ocean to cause a tsunami, or on land, but I think people should keep in mind that this is no dinosaur (or humanity) killer asteroid, which was an estimated 10,000 m. on a side, vs. 250 for Apophis (and a correspondingly far smaller mass.)

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Here's one account of plans to deal with such a threat:

http://www.telegraph.co.uk/news/main.jhtml...25/waster25.xml

I think they exaggerate the frequency and severity of the impacts.

They claim that a 1-mile diameter asteroid would wipe out an entire continent and blanket the globe in debris, and that this should happen "once every few hundred thousand years".

If we assume that one of these hits every 300,000 years, over the past 3 billion years we should have had 10,000 of these continental-killers by now! :)

Numbers like that can't possibly be right--if asteroids collisions are supposed to be this extremely catastrophic and frequent, how are we sitting here now talking about it now?

Also, I was under the impression that the theory was no longer held that a giant asteroid is what killed the dinosaurs. If the dinosaurs were all killed out suddenly, how could they have had time to evolve into birds?

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I think they exaggerate the frequency and severity of the impacts.

To add a bit more onto what I said:

There is a lot of empty space out there, and the Earth is an extremely small target to hit. Sometimes I don't think people realize just how vast the universe is, compared to how tiny and far apart the things within it are spread.

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To add a bit more onto what I said:

There is a lot of empty space out there, and the Earth is an extremely small target to hit. Sometimes I don't think people realize just how vast the universe is, compared to how tiny and far apart the things within it are spread.

The asteroids come from the asteroid belt between Mars and Jupiter. They are pretty close.

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