Open cluster
M48 (M48)
In Hydra (Hya) • Magnitude 5.5 • 54 arcminutes
Open the free AstroPlanner with M48 pre-selected, scored against your telescope, location, and the live cloud forecast.
A large, scattered open cluster in Hydra whose stars span nearly the area of the full Moon. Like M47, it was a "lost" Messier object for decades due to an error in the recorded coordinates, and wasn't definitively confirmed until 1934.
M48 at a glance
| Catalog IDs | M48, N 2548 |
| Type | Open cluster |
| Constellation | Hydra (Hya) |
| Right ascension | 08h 13m 48s |
| Declination | -05° 47' 60" |
| Apparent magnitude | 5.50 |
| Angular size | 54.0 × 54.0 arcmin |
| Max altitude at 45°N | 39° |
| Best imaging months | Oct, Nov, Dec |
How to image M48
M48 sits in the constellation Hydra at right ascension 08h 13m 48s and declination -05° 47' 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.