Asteroid: Doomsday or Payday?
The asteroid that exploded over Siberia--injuring more than 1,000 and damaging buildings in six cities--was a shocking reminder that Earth is a target in a cosmic shooting range. From the width of a football field to the size of a small city, these space rocks have the potential to be killers. In a collision with Earth, they could set off deadly blast waves, raging fires and colossal tidal waves.
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