
The near-Earth object, named 2012 DA14 after it was discovered last year by astronomers from an observatory in La Sagra in southern Spain, is 45 metres in diameter.
The asteroid is large enough to potentially devastate a large city if it struck Earth, which NASA scientists have ruled out.
The fly-by came the same day a meteor broke apart in the atmosphere over central Russia, injuring around 1,000 people as a shockwave blew out windows and collapsed some walls.
The two events were not related. NASA said the meteor was still being analysed, but that it had travelled from north to south, while thea steroid is moving on an opposite course from south to north.//DPA