An asteroid the size of the Gibraltar rock will be the largest asteroid to come this close to Earth since 2004. On Wednesday, the object is expected to pass close to our planet, zooming by at a distance of just over a million miles (1.8 million km), but with no chance of impact. Smaller asteroids regularly come closer than this , but this will be the largest asteroid to come this close to Earth since 2004, flying by at only about 4.6 times the distance from the Earth to the Moon, 1.1 million miles.
http://www.telegraph.co.uk/science/2017/04/19/large-asteroid-pass-close-earth-wednesday/
