Gamma Sagittae

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Gamma Sagittae
Diagram showing star positions and boundaries of the Sagitta constellation and its surroundings
Cercle rouge 100%.svg

Location of γ Sagittae (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Sagitta
Right ascension 19h 52m 06.36s
Declination +19° 29' 31.5"
Apparent magnitude (V) +3.51
Distance 274 ly
(84 pc)
Spectral type K5III
Other designations
γ Sagittae, γ Sge, Gamma Sge, 12 Sagittae, BD+19 4229, FK5 752, GC 27672, HD 189319, HIP 98337, HR 7635, PPM 137344, SAO 105500

Gamma Sagittae (Gamma Sge, γ Sagittae, γ Sge) is the brightest star in constellation Sagitta and is an orange K-type giant with an apparent magnitude of +3.51. It is approximately 274 light years from Earth and radiates at a power 640 times that of Sun. With a mass of 2.5 times that of the Sun, Gamma Sagittae began life 750 million years ago as a white class B9 star.[1]

Gamma Sagittae is moving through the Galaxy at a speed of 42.9 km/s relative to the Sun. It is projected Galactic orbit carries it between 20,300 and 25,900 light years from the center of the Galaxy.[2]

Gamma Sagittae will come closest to the Sun 1.4 million years from now when it will brighten to magnitude 2.44 from a distance of 158 light years.[2]

Naming[edit]

In Chinese, 左旗 (Zuǒ Qí), meaning Left Flag, refers to an asterism consisting of γ Sagittae, α Sagittae, β Sagittae, δ Sagittae, ζ Sagittae, 13 Sagittae, 11 Sagittae, 14 Sagittae and ρ Aquilae. Consequently, γ Sagittae itself is known as 左旗五 (Zuǒ Qí wǔ, English: the Fifth Star of Left Flag.)[3]

References[edit]