The 20 - 44 metre wide asteroid 2013 XY20 will make a close pass (15.5 lunar distances, 0.0399 AU), travelling at 2.18 km/second, to the Earth-Moon system on the 16th December, 2013 @ 13:51 UT ±00:40.
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The Lunar Distance (LD), the distance between Earth and the Moon, equals 384,401 km, (or 0.00256 AU).
