Ι_Ophiuchi
Iota Ophiuchi
Star in the constellation Ophiuchus
ι Ophiuchi, Latinized as Iota Ophiuchi, is a single[11] star in the equatorial constellation of Ophiuchus, positioned near the constellation border with Hercules. It makes a naked-eye double with nearby Kappa Ophiuchi,[12] appearing as a faint, blue-white hued star with an apparent visual magnitude of 4.39.[2] The star is approximately 245 light years from the Sun based on parallax,[1] but is drifting closer with a radial velocity of −19 km/s.[6]
This object is a B-type main-sequence star with a stellar classification of B8V.[4] It is an estimated 217[9] million years old with a moderately high rate of spin, showing a projected rotational velocity of 124 km/s.[3] The star has 3.1[3] times the mass of the Sun and around 2.8[7] times the Sun's radius. Iota Ophiuchi is radiating 141[3] times the luminosity of the Sun from its photosphere at an effective temperature of 11,220 K.[3] It displays an infrared excess, suggesting the presence of circumstellar material.[13]