The 7 - 16 metre wide asteroid 2015 RW2 made a close pass (5.1 LD, 0.0132 AU) travelling at 6.63 km/second, to the Earth-Moon system on the 4th September 2015 @ 19:46 UT ±00:04.
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The Lunar Distance (LD), the distance between Earth and the Moon, equals 384,401 km, (or 0.00256 AU).