Globular cluster
M68 (M68)
In Hydra (Hya) • Magnitude 9.7 • 11 arcminutes
Open the free AstroPlanner with M68 pre-selected, scored against your telescope, location, and the live cloud forecast.
A loose, faint globular cluster whose stars are among the most "metal-poor" known, meaning they formed very early in the universe before supernovae had enriched space with heavy elements. These stars are essentially a time capsule from the universe's first generation, before iron, oxygen, and the building blocks of rocky planets existed.
M68 at a glance
| Catalog IDs | M68, N 4590 |
| Type | Globular cluster |
| Constellation | Hydra (Hya) |
| Right ascension | 12h 39m 29s |
| Declination | -26° 44' 24" |
| Apparent magnitude | 9.67 |
| Surface brightness | 13.1 mag/arcsec² |
| Angular size | 11.0 × 11.0 arcmin |
| Max altitude at 45°N | 18° |
| Best imaging months | Dec, Jan, Feb |
How to image M68
M68 sits in the constellation Hydra at right ascension 12h 39m 29s and declination -26° 44' 24". 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.