The 110 - 250 metre wide asteroid 2007 SQ6 made a close pass (67.1 LD, 25,800,000 kms), travelling at 10km/s, to the Earth-Moon system on the 14th April 2009.
The Lunar Distance (LD), the distance between Earth and the Moon, equals 384,401 km, (or 0.00256 AU).