Orbital elements:
2003 WH166 PHA, Earth MOID = 0.0046 AU
Epoch 2012 Mar. 14.0 TT = JDT 2456000.5 MPC
M 0.18022 (2000.0) P Q
n 0.36627342 Peri. 328.59067 -0.90522054 -0.42494004
a 1.9346353 Node 186.26290 +0.39234056 -0.83457563
e 0.5557836 Incl. 0.69284 +0.16323192 -0.35058448
P 2.69 H 22.0 G 0.15 U 1
The 110 - 250 metre wide asteroid 2003 WH166 will make a close pass (19.8 lunar distances, 0.0509 AU), travelling at 13.49 km/second, to the Earth-Moon system on the 23rd April, 2012 @ 12:44 UT ±1 day 19:39.