* Astronomy

Orbital elements:
2012 SS56                                                Earth MOID = 0.0543 AU
Epoch 2012 Sept. 30.0 TT = JDT 2456200.5                MPC
M   7.35485              (2000.0)            P               Q
n   0.37986009     Peri.  163.77168     +0.97144005     +0.23188308
a   1.8882244      Node   184.02212     -0.19609565     +0.90399658
e   0.4470719      Incl.   45.86831     +0.13360661     -0.35919413
P   2.59           H   22.0           G   0.15           U   7

MPEC 2012 - S77

The 100 - 230 metre wide asteroid 2012 SS56 made a close pass (23.6 lunar distances, 0.0607 AU), travelling at 25.60 km/second, to the Earth-Moon system on the 25th September, 2012 @ 08:31 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).