Globular cluster
Sagittarius Cluster (M22)
In Sagittarius (Sgr) • Magnitude 5.1 • 32 arcminutes
Open the free AstroPlanner with Sagittarius Cluster pre-selected, scored against your telescope, location, and the live cloud forecast.
One of the nearest and brightest globular clusters, visible to the naked eye at just 10,400 light-years away. It is one of only four known globular clusters to contain a planetary nebula within it — meaning a star inside this stellar city has already lived, died, and puffed its outer layers into space.
Sagittarius Cluster at a glance
| Catalog IDs | M22, N 6656 |
| Type | Globular cluster |
| Constellation | Sagittarius (Sgr) |
| Right ascension | 18h 36m 25s |
| Declination | -23° 53' 60" |
| Apparent magnitude | 5.10 |
| Surface brightness | 12.3 mag/arcsec² |
| Angular size | 32.0 × 32.0 arcmin |
| Max altitude at 45°N | 21° |
| Best imaging months | Mar, Apr, May |
How to image Sagittarius Cluster
Sagittarius Cluster sits in the constellation Sagittarius at right ascension 18h 36m 25s and declination -23° 53' 60". To frame and integrate it well, AstroPlanner will compute the optimal moonless window for tonight from your location, the field-of-view fit against your sensor and focal length, the suggested total integration time given your aperture and sky Bortle class, and a cloud-aware schedule that drops it from the plan if your nearest cloud forecast spike overlaps the best altitude window.