Asteroid passes Earth

While you were sleeping, Earth had a relatively close encounter with a small asteroid.
    
The space rock was on track to pass within about 44,000 kilometres of Antarctica overnight.
    
NASA scientist Michael Kelley says that's ``pretty close'' as these things go.
    
There was never any chance the asteroid would hit the planet, but future ones might.
   
That's why NASA planned to use the flyby to run a sort of cosmic fire drill.