56 Sagittarii is a single[11] star in the southern constellation of Sagittarius. It has the Bayer designation f Sagittarii, while 56 Sagittarii is the Flamsteed designation. This object is visible to the naked eye as a faint, orange-hued point of light with an apparent visual magnitude of 4.87.[2] It is located approximately 208 light years away from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +22 km/s.[6]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 19h 46m 21.73912s[1] |
| Declination | −19° 45′ 40.0132″[1] |
| Apparent magnitude (V) | 4.87[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch[3] |
| Spectral type | K0+III[4] |
| U−B color index | +0.96[5] |
| B−V color index | +1.06[5] |
| Astrometry | |
| Radial velocity (Rv) | +22.07[6] km/s |
| Proper motion (μ) | RA: −129.40[1] mas/yr Dec.: −90.55[1] mas/yr |
| Parallax (π) | 15.71 ± 0.23 mas[1] |
| Distance | 208 ± 3 ly (63.7 ± 0.9 pc) |
| Absolute magnitude (MV) | 0.85[2] |
| Details | |
| Mass | 1.77[7] M☉ |
| Radius | 11[6] R☉ |
| Luminosity | 58.97[2] L☉ |
| Surface gravity (log g) | 2.58[8] cgs |
| Temperature | 4,750[9] K |
| Metallicity [Fe/H] | −0.07[8] dex |
| Rotational velocity (v sin i) | 1.9[6] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an aging giant star with a stellar classification of K0+III,[4] having exhausted the supply of hydrogen at its core and expanded to 11[6] times the Sun's radius. It is a red clump giant,[3] which means it is on the horizontal branch and is generating energy through helium fusion at its core. The star has 1.8[7] times the mass of the Sun and is radiating 59[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,750 K.[9]
References
edit- ^ a b c d e f 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. S2CID 18759600. Vizier catalog entry
- ^ a b c d e 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. Vizier catalog entry
- ^ a b 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 Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373.
- ^ a b Mermilliod, J. C. (2006). "Homogeneous Means in the UBV System (Mermilliod 1991)". VizieR On-line Data Catalog: II/168. Originally Published in: Institut d'Astronomie. 2168. Bibcode:2006yCat.2168....0M.Vizier catalog entry
- ^ 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. S2CID 121883397.
- ^ a b Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures". Astronomy and Astrophysics. 352: 555–562. arXiv:astro-ph/9911002. Bibcode:1999A&A...352..555A. Vizier catalog entry
- ^ a b Wu, Yue; et al. (2010). "Coudé-feed stellar spectral library – atmospheric parameters". Astronomy & Astrophysics. 525: A71. arXiv:1009.1491. Bibcode:2011A&A...525A..71W. doi:10.1051/0004-6361/201015014. S2CID 53480665.
- ^ a b Gontcharov, G. A. (2009). "Red giant clump in the Tycho-2 catalogue". Astronomy Letters. 34 (11): 785–796. arXiv:1607.00619. Bibcode:2008AstL...34..785G. doi:10.1134/S1063773708110078. S2CID 73524157. Vizier catalog entry
- ^ "f Sgr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-07-27.
- ^ 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, S2CID 14878976.