Space is littered with rocks, pebbles, and other debris left over from the birth of the solar system four and a half billion years ago. When one of these rocks slams into Earth's atmosphere, friction heats the rock and produces a flash of light that scientists call a meteor -- and many nonscientists call a falling star. And last year, for the first time, scientists managed to recover pieces of a space rock that had been discovered and tracked before it hit Earth.
The story began last October, when an astronomer in Arizona discovered an asteroid that was designated 2008 TC3. It was only about 10 feet across, but this was no ordinary asteroid. Calculations showed that it was on a collision course with Earth. And sure enough, just 19 hours later it smashed into the African nation of Sudan.
In December, scientists traveled to Sudan, hoping to find pieces of the fallen asteroid, known as meteorites. They searched the desert and succeeded in spectacular fashion -- they found hundreds of meteorites.
Observations of the asteroid before its impact, as well as studies of the meteorites themselves, indicate that the asteroid was of a rare type. It may have been a fragment of a larger asteroid of the same type.
Earth was born billions of years ago when asteroids smashed together and grew into a planet. So this asteroid's crash to Earth was a miniature reenactment of our planet's birth, four and a half billion years ago.
Script by Ken Croswell, Copyright 2009
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