20 Ceti is a single[9] star located around 590[1] light years away in the equatorial constellation of Cetus. It is faintly visible to the naked eye with apparent magnitude is 4.76.[2] The Bright Star Catalogue has this star classified as M0III,[10] matching an aging red giant star that has consumed the hydrogen at its core and expanded. Houk and Swift (1999) listed an earlier class of K5 III.[3] It has around 60 times the Sun's radius and is radiating about 800 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,700 K.[7]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cetus |
| Right ascension | 00h 53m 00.49452s[1] |
| Declination | −01° 08′ 39.3317″[1] |
| Apparent magnitude (V) | 4.76[2] |
| Characteristics | |
| Spectral type | K5 III[3] |
| U−B color index | +1.91[4] |
| B−V color index | +1.56[4] |
| Astrometry | |
| Radial velocity (Rv) | +16.22±0.28[5] km/s |
| Proper motion ( | RA: +6.99[1] mas/yr Dec.: −15.66[1] mas/yr |
| Parallax ( | 5.56 ± 0.22 mas[1] |
| Distance | 590 ± 20 ly (180 ± 7 pc) |
| Absolute magnitude (MV) | −1.58[6] |
| Details[7] | |
| Radius | 65.93+2.13 −2.25 R☉ |
| Luminosity | 754.8±52.6 L☉ |
| Surface gravity (log g) | 1.63 cgs |
| Temperature | 3,724±35 K |
| Other designations | |
| Database references | |
| SIMBAD | data |
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.
- ^ a b Ducati, J. R. (2002), "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system", CDS/ADC Collection of Electronic Catalogues, 2237, Bibcode:2002yCat.2237....0D.
- ^ 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- ^ a b Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, Bibcode:1986EgUBV........0M.
- ^ Famaey, B.; Pourbaix, D.; Frankowski, A.; Van Eck, S.; Mayor, M.; Udry, S.; Jorissen, A. (2009), "Spectroscopic binaries among Hipparcos M giants", Astronomy and Astrophysics, 498 (2): 627, arXiv:0901.0934, Bibcode:2009A&A...498..627F, doi:10.1051/0004-6361/200810698, S2CID 18739721.
- ^ Groenewegen, M. A. T. (April 2012), "Infrared excess around nearby red giant branch stars and Reimers law", Astronomy & Astrophysics, 540: 21, Bibcode:2012A&A...540A..32G, doi:10.1051/0004-6361/201118287, A32.
- ^ a b Baines, Ellyn K.; Thomas Armstrong, J.; Clark, James H.; Gorney, Jim; Hutter, Donald J.; Jorgensen, Anders M.; Kyte, Casey; Mozurkewich, David; Nisley, Ishara; Sanborn, Jason; Schmitt, Henrique R.; Van Belle, Gerard T. (2021). "Angular Diameters and Fundamental Parameters of Forty-four Stars from the Navy Precision Optical Interferometer". The Astronomical Journal. 162 (5): 198. arXiv:2211.09030. Bibcode:2021AJ....162..198B. doi:10.3847/1538-3881/ac2431. S2CID 238998021.
- ^ "20 Cet". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved December 26, 2018.
- ^ 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.
- ^ Hoffleit, D.; Warren, Jr., W. H. (1991), The Bright Star Catalogue (5th Revised ed.), New Haven: Yale University Observatory, Bibcode:1991bsc..book.....H.