NGC 5866
| NGC 5866 | |
|---|---|
NGC 5866, as observed by the Hubble Space Telescope (HST) | |
| Observation data (J2000 epoch) | |
| Constellation | Draco |
| Right ascension | 15h 06m 29.5s |
| Declination | +55° 45′ 48″ |
| Redshift | 0.002518±0.000017 |
| Heliocentric radial velocity | 755±5 km/s |
| Galactocentric velocity | 901±8 km/s |
| Distance | 50 ± 3 Mly (15.3 ± 0.7 Mpc) |
| Apparent magnitude (V) | 9.9 |
| Characteristics | |
| Type | SA0+; Sy |
| Size | 23.44 kiloparsecs (76,000 light-years) (diameter; D25 isophote) |
| Apparent size (V) | 4.7′ × 1.9′ |
| Notable features | The galaxy is viewed edge on |
| Other designations | |
| Spindle Galaxy, UGC 9723, PGC 53933 | |
NGC 5866 (also called the Spindle Galaxy or possibly Messier 102) is a lenticular galaxy in the constellation Draco. NGC 5866 was most likely discovered by Pierre Méchain or Charles Messier in 1781, and independently found by William Herschel in 1788. Measured orbital velocities of its globular cluster system imply that dark matter makes up only 34%±45% of the mass within 5 effective radii, a notable paucity.