Gamma Sagittae

γ Sagittae
Location of γ Sagittae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Sagitta
Right ascension 19h 58m 45.42823s
Declination +19° 29 31.7261
Apparent magnitude (V) +3.47
Characteristics
Evolutionary stage Red giant branch
Spectral type M0 III
U−B color index +1.93
B−V color index +1.57
Astrometry
Radial velocity (Rv)−34.0±0.2 km/s
Proper motion (μ) RA: +65.005 mas/yr
Dec.: +22.72 mas/yr
Parallax (π)11.3375±0.1652 mas
Distance288 ± 4 ly
(88 ± 1 pc)
Absolute magnitude (MV)−1.11
Details
Mass0.88+0.05
−0.02
 M

0.9±0.2 M
1.3±0.4 M
1.77 M
Radius57.71+0.86
−0.88
 R
Luminosity (bolometric)697±30 L
Surface gravity (log g)1.06±0.04 cgs
Temperature3,904±30 K
Metallicity [Fe/H]−0.26±0.06 dex
Age2.35 Gyr
Other designations
γ Sge, 12 Sagittae, BD+19°4229, FK5 752, GC 27672, HD 189319, HIP 98337, HR 7635, SAO 105500, PPM 137344
Database references
SIMBADdata

Gamma Sagittae, Latinized from γ Sagittae, is the brightest star in northern constellation of Sagitta. A single star, it is visible to the naked eye with an apparent visual magnitude of +3.47. Based upon an annual parallax shift of 12.62 mas as seen from Earth, it is located about 288 light-years from the Sun. It is moving closer to the Sun with a radial velocity of −34 km/s.

This is a red giant star with a stellar classification of M0 III. It is most likely (94% chance) on the red-giant branch of its evolutionary lifespan, fusing hydrogen along a shell to generate energy. The star is around 2.35 billion years old with roughly 58 times the Sun's radius. Mass estimates range from 0.9 to 1.8 times the mass of the Sun. It is radiating nearly 700 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,904 K.