The 22 - 50 metre wide asteroid 2012 HK31 will make a close pass (70.3 lunar distances, 0.1807 AU), travelling at 3.86 km/second, to the Earth-Moon system on the 20th December, 2012 @ 02:33 UT ±00:11.
Update: The 22 - 50 metre wide asteroid 2012 HK31 will make a close pass (13.1 lunar distances, 0.0336 AU), travelling at 3.03 km/second, to the Earth-Moon system on the 4th June, 2012 @ 00:30 UT ±00:03.
Orbital elements:
2012 HK31 Earth MOID = 0.0145 AU
Epoch 2012 Mar. 14.0 TT = JDT 2456000.5 MPC
M 231.53170 (2000.0) P Q
n 0.88713705 Peri. 96.77831 +0.76899486 +0.63868176
a 1.0726933 Node 223.53277 -0.60093254 +0.70780784
e 0.1217631 Incl. 2.25199 -0.21800684 +0.30181727
P 1.11 H 25.7 G 0.15 U 9
The 20 - 45 metre wide asteroid 2012 HK31 will make a close pass (13.7 lunar distances, 0.0353 AU), travelling at 2.84 km/second, to the Earth-Moon system on the 6th June, 2012 @ 02:58 UT ±2 days08:36.