* Astronomy

Orbital elements:
2011 ST12                                                Earth MOID = 0.0265 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5                 MPC
M 278.55309              (2000.0)            P               Q
n   0.83327029     Peri.   88.79380     +0.12445698     -0.99216134
a   1.1184385      Node   354.02168     +0.86203071     +0.11372917
e   0.2163073      Incl.    6.19554     +0.49133850     +0.05178377
P   1.18           H   26.5           G   0.15           U   6

MPEC 2011 - S21

The 14 - 31 metre wide asteroid 2011 ST12 will make a close pass (10.5 lunar distances, 0.0271 AU), travelling at 6.58 km/second, to the Earth-Moon system on the 29th September, 2011 @ 14:58 UT ±00:11.

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