sbcanada
New Member
(CNN) -- An asteroid the size of a football field passed extremely close to Earth last week but it remained undetected until days later, astronomers said Thursday.
The space rock missed our planet Friday by only 75,000 miles (120,000 km), about one-third the distance to the moon, making the near collision one of the closest ever recorded.
Cruising at 6.2 miles (10 km) per second, the big boulder could have unleashed some major firepower had it struck, according to the NEO (Near Earth Objects) Information Center in Leicester, England.
The destructive force might have been comparable to an asteroid or comet that exploded over Siberia in 1908, which flattened 77 square miles (2,000 square km) of trees, according to the NEO.
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If a really big asteroid actually hits the earth, we probably won't know about it until we're all dead.