Segue 1
| Segue 1 | |
|---|---|
| Observation data (J2000 epoch) | |
| Constellation | Leo |
| Right ascension | 10h 07m 04s |
| Declination | 16° 04′ 55″ |
| Distance | 75 ± 6.5 kly (23 ± 2 kpc) |
| Apparent magnitude (V) | 13.8 ± 0.5 |
| Characteristics | |
| Type | dSph or GC |
| Mass/Light ratio | 3400 (V) M☉/L☉ |
| Apparent size (V) | 8.8′ |
| Other designations | |
| Segue 1, PGC 4713559 | |
Segue 1 is a dwarf spheroidal galaxy or globular cluster situated in the Leo constellation and discovered in 2006 by the Sloan Digital Sky Survey. It is located at a distance of about 23 kpc (about 75,000 light years) from the Sun and moves away from the Sun with a velocity of about 206 km/s. Segue 1 has a noticeably elongated (ratio of axes ~ 2:1) shape with a half-light radius of about 30 pc. This elongation may be caused by tidal forces from the Milky Way galaxy if Segue 1 is being disrupted now.
The name is due to the fact that it was found by the SEGUE program, the Sloan Extension for Galactic Understanding and Exploration.