Globular cluster
M75 (M75)
In Sagittarius (Sgr) • Magnitude 9.2 • 6.0 arcminutes
Open the free AstroPlanner with M75 pre-selected, scored against your telescope, location, and the live cloud forecast.
One of the most distant and compact Messier globular clusters at about 67,500 light-years — practically on the far side of the Milky Way. The light you are capturing left M75 roughly 67,500 years ago, when modern humans were still sharing the planet with Neanderthals.
M75 at a glance
| Catalog IDs | M75, N 6864 |
| Type | Globular cluster |
| Constellation | Sagittarius (Sgr) |
| Right ascension | 20h 06m 07s |
| Declination | -21° 55' 12" |
| Apparent magnitude | 9.18 |
| Surface brightness | 13.0 mag/arcsec² |
| Angular size | 6.0 × 6.0 arcmin |
| Max altitude at 45°N | 23° |
| Best imaging months | Apr, May, Jun |
How to image M75
M75 sits in the constellation Sagittarius at right ascension 20h 06m 07s and declination -21° 55' 12". 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.