9_Hydrae
9 Hydrae
Star in the constellation Hydra
9 Hydrae is a single[9] star in the equatorial constellation of Hydra,[8] located 205 light years away from the Sun.[1] It is visible to the naked eye as a faint, yellow-orange hued star with an apparent visual magnitude of 4.87.[2] This body is moving closer to the Sun with a heliocentric radial velocity of −2 km/s.[1]
This is an aging giant star with a stellar classification of K0 III CNII,[3] where the suffix notation indicates an overabundance of cyanogen in the spectrum. It is a red clump giant,[10] which indicates it is on the horizontal branch and is generating energy through helium fusion at its core. The star has 1.7[7] times the mass of the Sun but, as a consequence of evolving away from the main sequence, its envelope has swollen to 11[1] times the Sun's radius. It is radiating 54 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,688 K.[6]