Globular cluster
M70 (M70)
In Sagittarius (Sgr) • Magnitude 9.1 • 8.0 arcminutes
Open the free AstroPlanner with M70 pre-selected, scored against your telescope, location, and the live cloud forecast.
A compact globular cluster in Sagittarius that became unexpectedly famous when amateur astronomer Thomas Bopp glanced near it on July 22, 1995, and spotted a faint fuzzy intruder — the comet that would become one of the most spectacular of the 20th century: Hale-Bopp.
M70 at a glance
| Catalog IDs | M70, N 6681 |
| Type | Globular cluster |
| Constellation | Sagittarius (Sgr) |
| Right ascension | 18h 43m 12s |
| Declination | -32° 17' 60" |
| Apparent magnitude | 9.06 |
| Surface brightness | 12.8 mag/arcsec² |
| Angular size | 8.0 × 8.0 arcmin |
| Max altitude at 45°N | 13° |
| Best imaging months | Mar, Apr, May |
How to image M70
M70 sits in the constellation Sagittarius at right ascension 18h 43m 12s and declination -32° 17' 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.