| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Cetus[1] |
| Right ascension | 02h 00m 00.308s[2] |
| Declination | −21° 04′ 40.194″[2] |
| Apparent magnitude (V) | 3.95[3] |
| Characteristics | |
| Spectral type | M0III[4] |
| U−B color index | +1.90[3] |
| B−V color index | +1.57[3] |
| Astrometry | |
| Radial velocity (Rv) | +18.00±0.70[5] km/s |
| Proper motion (μ) | RA: +133.922 mas/yr[2] Dec.: −24.341 mas/yr[2] |
| Parallax (π) | 10.2726±0.1451 mas[2] |
| Distance | 318 ± 4 ly (97 ± 1 pc) |
| Absolute magnitude (MV) | −0.77[1] |
| Details[6] | |
| Mass | 1.26±0.13 M☉ |
| Radius | 53.56±11.80 R☉ |
| Luminosity | 549.6±226.8 L☉ |
| Surface gravity (log g) | 1.15±0.18 cgs |
| Temperature | 3,822±148 K |
| Metallicity [Fe/H] | −0.06±0.10 dex |
| Age | 6.97±2.77 Gyr |
| Other designations | |
| υ Cet, 59 Cet, BD−21°358, FK5 71, HD 12274, HIP 9347, HR 585, SAO 167471[7] | |
| Database references | |
| SIMBAD | data |
Upsilon Ceti is a solitary[8] star in the equatorial constellation of Cetus. Its name is a Bayer designation that is Latinized from υ Ceti, and abbreviated Upsilon Cet or υ Cet. This star is visible to the naked eye with an apparent visual magnitude of 3.95.[3] Based upon an annual parallax shift of 10.27 mas,[2] it is located about 318 light-years (97 pc) from the Sun. It is drifting further away with a line of sight velocity component of +18 km/s.[5]
Nomenclature
[edit]This star was designated Upsilon Ceti by Bayer and 59 Ceti by Flamsteed. Flamsteed gave it the designation Upsilon2 Ceti to distinguish it from 56 Ceti, which he called Upsilon1. Flamsteed's superscripted designations, however, are not in general use today.[9]
For ancient Arabic astronomers, this star with η Cet (Deneb Algenubi), θ Cet (Thanih al Naamat), τ Cet and ζ Cet (Baten Kaitos), formed Al Naʽāmāt (النعامات), the Hen Ostriches[10] In Chinese, 鈇鑕 (Fū Zhì), meaning Sickle, refers to an asterism consisting of υ Ceti, 48 Ceti and 56 Ceti.[11] Consequently, the Chinese name for υ Ceti itself is 鈇鑕四 (Fū Zhì sì, English: the Fourth Star of Sickle.)[12]
Properties
[edit]Upsilon Ceti is an evolved red giant star with a stellar classification of M0III and is listed as a standard for that class.[4] This suggests the star has consumed the supply of hydrogen at its core and expanded away from the main sequence. The star has previously been classified as K5/M0III,[13] an interesting example of one of the "gaps" in the Morgan-Keenan classification system, with K6-9 often not used for giant stars or used only to indicate a fraction of the way between K5 and M0.[4]
At an estimated age of seven billion years, there is an 84% chance that this star is on the red giant branch, or 16% to be on the horizontal branch. Stellar models based on the red giant branch status yield an estimated mass of around 126% of the Sun's mass and 54 times the radius of the Sun. This model indicates the star radiates around 550 times the solar luminosity from its outer atmosphere at an effective temperature of 3,822 K.[6]
References
[edit]- ^ a b 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. XHIP record for this object at VizieR.
- ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023), "Gaia Data Release 3. Summary of the content and survey properties", Astronomy and Astrophysics, 674: A1, arXiv:2208.00211, Bibcode:2023A&A...674A...1G, doi:10.1051/0004-6361/202243940, S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.
- ^ a b c 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 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.
- ^ a b Reffert, Sabine; et al. (2015), "Precise radial velocities of giant stars. VII. Occurrence rate of giant extrasolar planets as a function of mass and metallicity", Astronomy and Astrophysics, 574A (2): 116–129, arXiv:1412.4634, Bibcode:2015A&A...574A.116R, doi:10.1051/0004-6361/201322360, hdl:10722/215277, S2CID 59334290.
- ^ "ups Cet", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2026-03-19.
- ^ 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, S2CID 14878976.
- ^ Wagman, Morton (2003), Lost Stars, The McDonald & Woodward Publishing Company, p. 106, ISBN 0-939923-78-5.
- ^ Allen, R. H. (1963), Star Names: Their Lore and Meaning (Reprint ed.), New York: Dover Publications Inc., p. 162, ISBN 0-486-21079-0, retrieved 2010-12-12.
{{citation}}: CS1 maint: ignored ISBN errors (link) - ^ (in Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
- ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 10 日 Archived 2011-07-16 at the Wayback Machine
- ^ Houk, Nancy; Smith-Moore, M. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
External links
[edit]- Kaler, James B. (November 4, 2011), "Upsilon Ceti", Stars, University of Illinois, retrieved 2017-02-13.
- http://www.alcyone.de/cgi-bin/search.pl?object=HR0585 Archived 2016-03-03 at the Wayback Machine
- http://server3.wikisky.org/starview?object_type=1&object_id=714
