* Astronomy

The 210 - 470 metre wide asteroid 2005 YV128 will make a close pass (67.0 lunar distances, 0.1722 AU), travelling at 14.43 km/second, to the Earth-Moon system on the 23rd December 2013 @ 12:51 UT ±00:01. 

See more

The Lunar Distance (LD), the distance between Earth and the Moon, equals 384,401 km, (or 0.00256 AU).