The 320 - 710 metre wide asteroid 1999 SK10 will make a close pass (71.5 lunar distances, 0.1838 AU), travelling at 11.48 km/second, to the Earth-Moon system on the 21st February 2014 @ 08:11 UT ±00:01.
See moreThe Lunar Distance (LD), the distance between Earth and the Moon, equals 384,401 km, (or 0.00256 AU).