Research sheds new light on asteroid disaster (AP/CNN)

[eppur_se_muova]

ALBUQUERQUE, New Mexico (AP) -- An asteroid that exploded over Siberia a century ago, leaving 800 square miles of scorched or blown down trees, wasn't nearly as large as previously thought, a researcher concludes, suggesting a greater danger for Earth.

According to supercomputer simulations by Sandia National Laboratories physicist Mark Boslough, the asteroid that destroyed the forest at Tunguska in Siberia in June 1908 had a blast force equivalent to one-quarter to one-third of the 10- to 20-megaton range scientists previously estimated.

Better understanding of what happened at Tunguska will allow for better estimates of risk that would allow policymakers to decide whether to try to deflect an asteroid or evacuate people in its path, he said.

"It's not clear whether a 10-megaton asteroid is more damaging than a Hurricane Katrina," Boslough said. "We can more accurately predict the location of an impact and its time better than we can a hurricane, so you really could get people out of there if it's below a certain threshold."

On Tuesday, an asteroid at least 800 feet long was making a rare close pass by Earth, but scientists said there was no chance of an impact. The closest approach of 2007 TU24 will be 334,000 miles -- about 1.4 times the distance of Earth to the moon. An actual collision of a similar-sized object with Earth occurs on average every 37,000 years.
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more: http://www.cnn.com/2008/TECH/space/01/29/asteroid.recalculated.ap/index.html

[Teaser]

1. Has it been established it was an asteroid

That's always been the explanation favored...

[Igel]

2. Looks that way.

I guess the final proof--excavation of the crater and finding bits of the meteorite--is yet future. Or at least unknown to me.

http://www.tfot.info/news/1070/in-search-of-the-tunguska-meteorite.html

[backwoodsbob]

3. heard an alternate theory

that it was a comet.Either way..interesting

[caraher]

4. I'm sure the History Channel has some other explanation

Hmmm... anti-matter or a passing black hole? A sudden tear in the fabric of spacetime?

remember, the most exotic explanation translates in the best ratings


(just in case... ;-) )

[Orsino]

5. A successful computer simulation is pretty good evidence. n/t