* Astronomy

The 33 - 74 metre wide asteroid 2013 RN43 will make a close pass (36.5 lunar distances, 0.0939 AU), travelling at 6.61 km/second, to the Earth-Moon system on the 20th September, 2013 @ 07:16 UT ±00:41. 

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