Asteroid heads for Earth, Russian astronomer claims
October 2, 2007An asteroid discovered three years ago could be a threat in 2029 when it crosses Earth's orbit, a Russian astronomer said Monday.
Boris Shustov, director of the Institute of Astronomy, said at a forum that the Apophis asteroid could have a bigger impact than an asteroid that hit Siberia in 1908, the Novosti news agency reported.
The Tunguska astral event affected 830 square miles and blasted 80 million trees. The force of the impact was about 1,000 times more powerful than the atomic bomb the United States dropped on Hiroshima, Japan, at the end of World War II and measured 5.0 on the Richter scale.
Apophis' predicted track would take it within 17,000 miles of Earth in 2029, Shustov said.
He said if the asteroid proves to be a threat, the Hollywood scenario of destroying it is likely to be more harmful than helpful. Instead, a micro-satellite could nudge it into a safer orbit.
"To blast an asteroid, as some hot shots suggest, is quite an unpredictable step, and a more cautious approach is welcomed now," he said.
Copyright 2007 by United Press International
22 hours ago
Talk about going from bad to worse. Then instead of having one or 2 big pieces hitting Earth, you have a million littler pieces, all of which can still do serious damage. The total kinetic energy of the strike is still the same either way.
Human civilization has been around for thousands of years. So the reason for suddenly looking for objects from space is....? Good news stories? Funding for obscure engineers and scientists looking for a meal ticket?
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I don't know how big they think the Apophos Asteroid is, but disintegration IS better than a slug. The asteroid in the Armageddon movie was like 500 kilometer diameter, which was very unrealistic even for a nuke to split that size object.
However, a "normal" object of a kilometer or two diameter could be blown apart by a well placed nuke, redirecting most of the material just enough to cause it to miss, and spreading out any residual impacts over a larger area and time.
It is better for many car or building size objects to enter the atmosphere a few at a time over several hours or days, than it is for an object the size of a small mountain to hit all at once. Smaller objects have a greater surface area per unit mass, which makes them burn up in atmostphere easier than a large one.
So the benefit of disintegration is manifold:
1) spread damage out over space and time.
2) burn up more of the object in the atmosphere, reducing the total mass, and therefore force, which reachers earth's surface.
3) Some of the material may miss the earth entirely.
I'll take the pennies because they are more likely to be slowed by air resistance and spread out, and also much of the energy will miss me, whereas a copper slug will hit all at once and smash me to oblivion.