CBNNews.com - Astronomers say a giant space rock that was 115 miles wide and about the size of a ten-story building flew passed earth Monday.

It was spotted about 72,000 miles away from earth.

A similar but smaller asteroid exploded in 1908 destroying the Siberian forest.

That asteroid's force was equivalent to 1,000 World War II atomic bombs.

Some scientists speculate these type of asteroids could hit earth once every 200 years.