The 28 - 62 metre wide asteroid 2011 SA121 made a close pass (29.4 lunar distances, 0.0756 AU), travelling at 12.28 km/second, to the Earth-Moon system on the 27th September, 2011 @ 01:48 UT ±00:22.
Orbital elements:
2011 SA121 Earth MOID = 0.0665 AU
Epoch 2011 Aug. 27.0 TT = JDT 2455800.5 MPC
M 358.74450 (2000.0) P Q
n 0.57177342 Peri. 147.39587 +0.90323962 +0.42612154
a 1.4376508 Node 187.90019 -0.42798464 +0.90315048
e 0.2798412 Incl. 21.68174 +0.03142203 +0.05234151
P 1.72 H 24.9 G 0.15 U 8