Omega_Sagittarii
Omega Sagittarii
Binary star system in the constellation of Sagittarius
Omega Sagittarii, which is Latinized from ω Sagittarii, is a binary star system in the constellation of Sagittarius,[9] near the eastern constellation border with Capricornus. It is formally named Terebellum /tɛrɪˈbɛləm/.[10][11] This system has a yellow hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.70.[2] It is located at a distance of 76 light years away from the Sun based on parallax,[1] and is drifting closer with a radial velocity of −16 km/s.[1] The position of this star near the ecliptic means it is subject to lunar occultations.[12]
The members of this system orbit each other with a period of 4.6892 yr and an eccentricity of 0.82.[6] The visible component is a G-type subgiant star with a stellar classification of G5 IV.[3] It is three[7] billion years old and is spinning with a projected rotational velocity of 5.6 km/s.[8] The star is radiating seven[1] times the luminosity of the Sun from its photosphere at an effective temperature of 5,499 K.[7]