60 Serpentis
60 Serpentis, also known as c Serpentis, is a single,[7] orange-hued star in Serpens Cauda, the eastern section of the constellation Serpens. It is faintly visible to the naked eye with an apparent visual magnitude of 5.38.[2] The distance to this star, as estimated from its annual parallax shift of 25.16±0.31 mas,[1] is approximately 130 light years. It is moving further from the Sun with a heliocentric radial velocity of +28 km/s,[4] having approached as close as 107 ly (32.7 pc) some 1.9 million years ago.[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Serpens |
| Right ascension | 18h 29m 40.97948s[1] |
| Declination | −01° 59′ 07.1058″[1] |
| Apparent magnitude (V) | 5.38[2] |
| Characteristics | |
| Spectral type | K0 III[3] |
| B−V color index | 0.961±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | +28.36±0.34[4] km/s |
| Proper motion (μ) | RA: −85.35[1] mas/yr Dec.: −34.31[1] mas/yr |
| Parallax (π) | 25.16 ± 0.31[1] mas |
| Distance | 130 ± 2 ly (39.7 ± 0.5 pc) |
| Absolute magnitude (MV) | 1.25±0.07[5] |
| Details | |
| Mass | 1.81±0.49[5] M☉ |
| Radius | 8[4] R☉ |
| Luminosity | 35[4] L☉ |
| Surface gravity (log g) | 2.92±0.11[5] cgs |
| Temperature | 5,059±92[5] K |
| Metallicity [Fe/H] | −0.08[4] dex |
| Rotational velocity (v sin i) | 3.9[4] km/s |
| Age | 1.26+0.19 −0.16[5] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved K-type giant star with a stellar classification of K0 III,[3] having used up its core hydrogen and expanded. At the age of around 1.26 billion years, it currently belongs to the so-called "red clump", which indicates it is on the horizontal branch and is generating energy through helium fusion at its core.[8] The star has an estimated 1.8[5] times the mass of the Sun and 8[4] times the Sun's radius. It is radiating 35[4] times the Sun's luminosity from its enlarged photosphere at an effective temperature of about 5,059 K.[5]
References
- van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357.
- 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.
- Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H.
- 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.
- Feuillet, Diane K.; et al. (2016), "Determining Ages of APOGEE Giants with Known Distances", The Astrophysical Journal, 817: 40, arXiv:1511.04088, Bibcode:2016ApJ...817...40F, doi:10.3847/0004-637X/817/1/40.
- "60 Ser". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-03-19.
- Eggleton, P. P.; Tokovinin, A. A. (September 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.
- 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.