Portal:Astronomy/Events/December 2011
| 4 December, 08:54 | Mercury at inferior conjunction |
| 6 December, 01:06 | Moon at apogee |
| 10 December, 14:33 | Full moon and total lunar eclipse |
| 14 December, 15:00 | Geminids peak |
| 16 December, 00:00 | Comet C/2011 W3 (Lovejoy) at maximum brightness |
| 22 December, 02:51 | Moon at perigee |
| 22 December, 05:30 | Earth at southern solstice |
| 23 December, 03:06 | Mercury at greatest western elongation |
| 23 December, 09:00 | Ursids peak |
| 24 December, 18:06 | New moon |
| 29 December | Pluto at conjunction |