Orbital elements:
2012 YR1 Earth MOID = 0.0010 AU
Epoch 2012 Sept. 30.0 TT = JDT 2456200.5 MPC
M 339.24101 (2000.0) P Q
n 0.33771941 Peri. 341.91902 +0.45013623 -0.89188699
a 2.0422020 Node 81.30926 +0.82464287 +0.39639915
e 0.5278904 Incl. 2.53724 +0.34255147 +0.21772760
P 2.92 H 26.6 G 0.15 U 8
The 13 - 30 metre wide asteroid 2012 YR1 made a close pass (5.8 lunar distances, 0.0150 AU), travelling at 8.52 km/second, to the Earth-Moon system on the 19th December, 2012 @ 10:13 UT ±00:05.