* Astronomy

The 510 - 1100 metre wide asteroid 2001 AF2 will make a close pass (70.5 lunar distances, 0.1812 AU), travelling at 21.31 km/second, to the Earth-Moon system on the 15th December, 2012 @ 16:59 UT ±00:01. 

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