omega1 Tauri
{{Short description|Star in the constellation Taurus}}
{{DISPLAYTITLE:Omega1 Tauri}}
{{other stars by Bayer designation|Omega Tauri{{!}}ω Tauri}}
{{Starbox begin
| name = Omega1 Tauri
}}
{{Starbox observe
| epoch = J2000.0
| constell = Taurus
}}
{{Starbox character
| u-b =
| variable =
}}
{{Starbox astrometry
| radial_v = {{Val|+24.75|0.02}}
| parallax = 11.22
| p_error = 0.70
}}
{{Starbox detail
| source =
| temperature = {{Val|4737|77|fmt=commas}}
}}
{{Starbox catalog
| names = {{odlist | B=ω1 Tau | F=43 Tau | BD=+19°672 | FK5=1115 | HD=26162 | HIP=19388 | HR=1283 | SAO=93785}}
}}
{{Starbox reference
| Simbad = ome01+Tau
}}
{{Starbox end}}
Omega1 Tauri is a solitary, orange hued star in the zodiac constellation of Taurus. It is faintly visible to the naked eye with an apparent visual magnitude of +5.51. Based upon an annual parallax shift of 11.22 mas as seen from Earth, it is located about 290 light years from the Sun.
This is an evolved K-type giant star with a stellar classification of K2 III. At the estimated age of 4.2 billion years, it is a red clump star that is generating energy by helium fusion at its core. Omega1 Tauri has about 1.5 times the mass of the Sun and has expanded to around 12 times the Sun's radius. It is radiating 57.5 times the Sun's luminosity from its photosphere at an effective temperature of 4,737 K. The radial velocity of this star shows no appreciable variation, and for this reason it is used as a radial velocity standard.
References
{{reflist|30em|refs=
| title=Validation of the new Hipparcos reduction
| last1=van Leeuwen | first1=F.
| journal=Astronomy and Astrophysics
| volume=474 | issue=2 | pages=653–664 | date=2007
| arxiv=0708.1752 | bibcode=2007A&A...474..653V
| doi=10.1051/0004-6361:20078357 | s2cid=18759600 | postscript=. }}
| last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
| title=A catalogue of multiplicity among bright stellar systems
| journal=Monthly Notices of the Royal Astronomical Society
| volume=389 | issue=2 | pages=869–879 | date=September 2008
| bibcode=2008MNRAS.389..869E | doi=10.1111/j.1365-2966.2008.13596.x
| doi-access=free | arxiv=0806.2878 | s2cid=14878976 | postscript=. }}
{{citation | display-authors=1
| last1=Massarotti | first1=Alessandro | last2=Latham | first2=David W.
| last3=Stefanik | first3=Robert P. | last4=Fogel | first4=Jeffrey
| title=Rotational and radial velocities for a sample of 761 HIPPARCOS giants and the role of binarity
| journal=The Astronomical Journal | postscript=.
| volume=135 | issue=1 | pages=209–231 | date=January 2008
| doi=10.1088/0004-6256/135/1/209 | bibcode=2008AJ....135..209M | doi-access=free }}
| title=Abundances in the Local Region. I. G and K Giants
| last1=Luck | first1=R. Earle
| journal=Astronomical Journal | postscript=.
| volume=150 | issue=3 | at=88 | year=2015
| bibcode=2015AJ....150...88L | doi=10.1088/0004-6256/150/3/88 |arxiv = 1507.01466 | s2cid=118505114 }}
| title=Red clump stars of the Milky Way - laboratories of extra-mixing
| display-authors=1 | last1=Tautvaišienė | first1=G.
| last2=Barisevičius | first2=G. | last3=Chorniy | first3=Y.
| last4=Ilyin | first4=I. | last5=Puzeras | first5=E.
| journal=Monthly Notices of the Royal Astronomical Society
| volume=430 | issue=1 | pages=621−627 | date=March 2013
| doi=10.1093/mnras/sts663 | doi-access=free
| bibcode=2013MNRAS.430..621T |arxiv = 1304.4393 | s2cid=119211439
}}
| display-authors=1 | last1=Hekker | first1=S.
| last2=Reffert | first2=S. | last3=Quirrenbach | first3=A.
| last4=Mitchell | first4=D. S. | last5=Fischer | first5=D. A.
| last6=Marcy | first6=G. W. | last7=Butler | first7=R. P.
| title=Precise radial velocities of giant stars. I. Stable stars
| journal=Astronomy and Astrophysics
| volume=454 | issue=3 | pages=943–949 | date=August 2006
| doi=10.1051/0004-6361:20064946 | bibcode=2006A&A...454..943H
| arxiv=astro-ph/0604502 | s2cid=119529768 | postscript=. }}
| title=ome01 Tau | access-date=2017-06-30 }}
}}
{{Stars of Taurus|state=collapsed}}
{{DEFAULTSORT:Omega1 Tauri}}
Category:Horizontal-branch stars