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We started our research in the Yahoo! Comets, Meteors, and Asteroids category. We found quite a bit of interesting information about "near earth objects," but failed to find the answer we wanted, so we headed back to the top page of Yahoo!. Hoping to find more detailed information on asteroids, we typed "biggest asteroid to hit the earth" in the Yahoo! search box. Terminal Reality, a student-built site hosted on Thinkquest, got us off to a good start. We discovered the following: The biggest asteroid to hit the Earth
this century was in Siberia on June 30, 1908. The rock was about 100,000 tons and the size of a large house. It shattered in the air, while about four miles from the ground, creating an explosion 2,000 times stronger than an atomic bomb! It demolished thousands of square miles of forestation. After perusing a few more sites, we realized that the answer to your question is pure conjecture, because the event in question probably took place millions and millions of years ago. According to an article in the Seattle Post-Intelligencer, researchers who analyzed the chemistry of ancient deposits in China and Japan hypothesize that a space rock three to seven miles wide hit the Earth about 251 million
years ago. This event led to the Permian-Triassic extinction event, or the "great dying." Scientists estimate that 90 percent of all ocean species and 70 percent of all land species vanished during this time. Catastrophic events like this can set off an immense wave of extremely hot vapor that rolls for hundreds of miles, killing everything in its path. Such an impact can also cause tidal waves and "send millions of tons of dust and vapor into the atmosphere to darken the sun for months and chill the Earth." A web page from the Science@NASA site dissects the "great dying" theory and argues that while a giant asteroid probably hit the earth about 250 million
years ago, it was not the primary cause of this massive extinction. Many scientists believe that Earth was experiencing severe volcanism when the asteroid hit, and the impact poured gasoline on the proverbial fire. As Luann Becker, a geologist at the University of California, Santa Barbara, says, "If life suddenly has all these different things happen to it and then you slam it with a rock the size of Mt. Everest -- boy! That's just really bad luck." Be on the look out for the asteroid known as 1950 DA. According to astronomers, there's a 1-in-300 chance the giant asteroid could hit the Earth. We have a bit of time to prepare, however. If estimates prove correct, and bad luck strikes again, the asteroid will hit in 2880.
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