11 Serpentis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 32m 57.93765s[1] |
| Declination | −01° 11′ 11.0412″[1] |
| Apparent magnitude (V) | 5.497[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch[2] |
| Spectral type | K0 III[3] |
| B−V color index | 1.092[2] |
| Astrometry | |
| Radial velocity (Rv) | −16.1±2.8[4] km/s |
| Proper motion (μ) | RA: −17.765[1] mas/yr Dec.: −42.217[1] mas/yr |
| Parallax (π) | 12.0563 ± 0.1290 mas[1] |
| Distance | 271 ± 3 ly (82.9 ± 0.9 pc) |
| Absolute magnitude (MV) | 0.83[5] |
| Details | |
| Mass | 1.27±0.35[6] M☉ |
| Radius | 11[7] R☉ |
| Luminosity | 50[7] L☉ |
| Surface gravity (log g) | 2.48±0.11[6] cgs |
| Temperature | 4,767±92[6] K |
| Metallicity [Fe/H] | −0.13[7] dex |
| Age | 2.75+0.88 −0.66[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
11 Serpentis is a single[9] star in the constellation of Serpens, located 271 light years away from the Sun. It has the Bayer designation A1 Serpentis,[10] 11 Serpentis is the Flamsteed designation. This object is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.497.[2] It is moving closer to the Earth with a heliocentric radial velocity of −16 km/s.[4]
This is an aging giant star with a stellar classification of K0 III,[3] a star that has used up its core hydrogen and has expanded. It is a red clump giant on the horizontal branch, which indicates it is generating energy through the fusion of helium at its core.[2] 11 Serpentis is 2.75 billion years old with 1.3[6] times the mass of the Sun and has 11[7] times the Sun's radius. It is radiating 50[7] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,767 K.[6]
References[edit]
- ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal, 539 (2): 732–741, arXiv:astro-ph/0003329, Bibcode:2000ApJ...539..732A, doi:10.1086/309278, S2CID 16673121.
- ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Ann Arbor, Michigan: Department of Astronomy, University of Michigan, Bibcode:1999MSS...C05....0H
- ^ a b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c d e f Feuillet, Diane K.; et al. (2016), "Determining Ages of APOGEE Giants with Known Distances", The Astrophysical Journal, 817 (1): 40, arXiv:1511.04088, Bibcode:2016ApJ...817...40F, doi:10.3847/0004-637x/817/1/40, S2CID 118675933.
- ^ a b c d e Massarotti, Alessandro; et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 Hipparcos Giants and the Role of Binarity", The Astronomical Journal, 135 (1): 209–231, Bibcode:2008AJ....135..209M, doi:10.1088/0004-6256/135/1/209
- ^ "11 Ser". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-21.
- ^ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976
- ^ Hoffleit, D. (July 1979), "Discordances in Star Designations", Bulletin d'Information du Centre de Données Stellaires, 17 (17): 38, Bibcode:1979BICDS..17...38H
