15 Cygni

Star in the constellation Cygnus Cygnus constellation map.svg center 280 right Red circle.svg 10 15 Cygni 555 492 Location of 15 Cygni (circled in red) J2000 Cygnus 19 44 16.60522 +37 21 15.6771 4.90 red clump G8 III 0.931 −23.62 0.21 +72.660 +35.708 11.0063 0.1188 0.19 2.30 12 93.3 4920 61 commas 2.8 −0.14 2.8 1.50 15 Cyg +37°3586 740 186675 97118 7517 68778 15+Cyg 15 Cygni is a single star in the northern constellation Cygnus. With an apparent visual magnitude of 4.90, it is a faint star but visible to the naked eye. The distance to 15 Cygni can be estimated from its annual parallax shift of 11.0 mas, which yields a separation of some 296 light years. It is moving closer to the Sun with a heliocentric radial velocity of −23.6 km/s. This is an aging giant star with a stellar classification of G8 III, having consumed the hydrogen at its core and evolved off the main sequence. It is a red clump giant, which means it is generating energy via helium fusion at its core. The star is 1.50 billion years old with 2.3 times the mass of the Sun, and has expanded to 12 times the Sun's radius. It is radiating 93 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,920 K. References 15 Cyg 2019-01-09 2048824680109512320 Stellar Parameters and Photospheric Abundances of Late-G Giants: Properties of the Targets of the Okayama Planet Search Program 1 Takeda Yoichi Sato Bun'ei Kambe Eiji Izumiura Hideyuki Masuda Seiji Ando Hiroyasu Publications of the Astronomical Society of Japan 57 1 109–125 February 2005 10.1093/pasj/57.1.109 2005PASJ...57..109T . free Abundances in the Local Region. I. G and K Giants The Astronomical Journal Luck R. Earle . 150 3 88 2015 2015AJ....150...88L 10.1088/0004-6256/150/3/88 1507.01466 118505114 The Perkins catalog of revised MK types for the cooler stars Keenan Philip C. McNeil Raymond C. Astrophysical Journal Supplement Series 71 245 1989 . 1989ApJS...71..245K 10.1086/191373 Massarotti Alessandro Latham David W. Stefanik Robert P. Fogel Jeffrey Rotational and Radial Velocities for a Sample of 761 Hipparcos Giants and the Role of Binarity 1 The Astronomical Journal 135 1 209–231 January 2008 10.1088/0004-6256/135/1/209 2008AJ....135..209M free Eggleton P. P. Tokovinin A. A. A catalogue of multiplicity among bright stellar systems Monthly Notices of the Royal Astronomical Society 389 2 869–879 September 2008 10.1111/j.1365-2966.2008.13596.x free 2008MNRAS.389..869E 0806.2878 14878976 . Alves David R. K-Band Calibration of the Red Clump Luminosity The Astrophysical Journal 539 2 732–741 August 2000 10.1086/309278 2000ApJ...539..732A . astro-ph/0003329 16673121 Category:G8III stars Category:Horizontal-branch stars Category:Cygnus (constellation) BD+37 3586 Cygni, 15 186675 097118 7517