A NASA graphic traces the asteroid 2009 VA's path within the moon's orbit and past
Earth. Each dot on the 2009 VA line indicates an hour of time along the route.
Asteroid-watchers say a space rock about as big as a garage came within 9,000 miles (14,000 kilometers) of Earth last Friday, just 15 hours after it was detected.
Experts quickly determined that the asteroid 2009 VA would miss us - and even if it came directly at us, it wouldn't have caused a catastrophe. Nevertheless, the close encounter serves as a reminder that someday a much bigger rock may well hit us and that it's best to be prepared.
In this week's recap of the event, NASA's Near-Earth Object Program Office reported that 2009 VA came well within the moon's orbit - so close, in fact, that the asteroid's orbital path was bent by Earth's gravitational pull.
NASA and other space agencies around the world have been keeping increasingly close track of near-Earth asteroids and comets, with a strong assist from amateur astronomers. In this case, the object was first detected by the Catalina Sky Survey at the University of Arizona. It was quickly identified by the Minor Planet Center in Cambridge, Mass., as a close-approaching asteroid. Then NASA experts worked out its orbit and gave the all-clear.
If 2009 VA had entered the atmosphere, it almost certainly would have blown itself up before hitting the ground - just as a larger asteroid did a month ago, without warning, in the skies over Indonesia. A somewhat smaller asteroid met a similar fate in the skies over Africa about 13 months ago. (Months later, students in Sudan found 4 kilograms (8.7 pounds) of meteorites that fell to Earth after last year's blast.)
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