Crikey! That was close!

Early on Tuesday morning an asteroid between 30-50m in size zoomed past the Earth, just 60,000km above the southwestern Pacific. I know that sounds like a long way away, but the moon is seven times that distance from here. No one has ever seen something that big come so close before. If it had hit New Zealand, it would be like having a nuclear bomb go off, and it would have devastated a large area. If it had hit the sea, it would have generated a tsunami. Astronomers first spotted it on Friday, and probably promptly crapped themselves until they realised that it's trajectory meant it wasn't going to hit us.

http://www.stuff.co.nz/science/2001262/Asteroid-bolts-past