Portal:Astronomy/Events/May 2011
| 3 May, 06:51 | New moon | 
| 7 May, 19:06 | Mercury at greatest western elongation | 
| 7 May, 23:00 | Eta Aquariids peak | 
| 15 May, 11:32 | Moon at perigee | 
| 17 May, 11:09 | Full moon | 
| 27 May, 10:02 | Moon at apogee | 
| 3 May, 06:51 | New moon | 
| 7 May, 19:06 | Mercury at greatest western elongation | 
| 7 May, 23:00 | Eta Aquariids peak | 
| 15 May, 11:32 | Moon at perigee | 
| 17 May, 11:09 | Full moon | 
| 27 May, 10:02 | Moon at apogee |