The 15 - 34 metre wide asteroid 2013 RF74 will make a close pass (5.5 lunar distances, 0.0142 AU), travelling at 10.56 km/second, to the Earth-Moon system on the 18th September, 2013 @ 16:53 UT ±00:01.
See more
The Lunar Distance (LD), the distance between Earth and the Moon, equals 384,401 km, (or 0.00256 AU).