Asterism in Aquarius
Messier 73 is probably the second least interesting object in Messier's catalog after Messier 40 (the latter is just a dim pair of stars). Charles Messier thought that this group of 4 stars was surrounded by some nebulosity and might be mistaken for a comet, so he included it in his list. Modern research has determined that Messier 73 is not a true cluster (in which the stars are actually close together) but a chance alignment of a few stars (which is called an asterism).
| Magnitude | 8.9 |
| Apparent Size | 1.4' |
| Distance (light yrs) | 2500 |
| Right Ascension | 20:58.9 |
| Declination | -12 38 |
| Field of View | 35' x 27' |
Image details: Exposure times of 5 minutes luminance, and 3 minutes each of red, green and blue, taken with an SBIG ST-8300M camera and a 12" Meade telescope at f/5.6.
December 2011