The 54 - 120 metre wide asteroid 2011 OX4 made a close pass (28.2 lunar distances, 0.0724 AU), travelling at 6.45 km/second, to the Earth-Moon system on the 24th July, 2011 @ 09:03 UT ±00:44.
Orbital elements:
2011 OX4 Earth MOID = 0.0724 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 9.11261 (2000.0) P Q
n 0.26043595 Peri. 324.84173 +0.49166213 +0.87060060
a 2.4284850 Node 334.59390 -0.78902978 +0.43667583
e 0.5536144 Incl. 2.40061 -0.36837529 +0.22664688
P 3.78 H 23.5 G 0.15 U 5