{{Short description|Variable star in the constellation Taurus}}{{distinguish|Upsilon Tauri}} {{Starbox begin}} {{Starbox image | image= {{Location mark |image=Taurus constellation map.svg|alt=|float=center|width=280 |label=|position=right |mark=Red circle.svg|mark_width=10|mark_link=Y Tauri |x=48|y=402 }} |caption=Location of Y Tauri (circled) }} {{Starbox observe |epoch=J2000 |constell=Taurus<ref name=constellation/> |ra={{RA|05|45|39.4101}}<ref name=edr3/> |dec={{DEC|+20|41|42.149}}<ref name=edr3/> |appmag_v=6.5 - 9.2<ref name=gcvs/> }} {{Starbox character |type=AGB<ref name=vdes2021/><ref name=guandalini2013/> |class=C6.5,4e(N3)<ref name=gcvs/> |b-v= |u-b= |variable=SRb<ref name=gcvs/> }} {{Starbox astrometry |radial_v=17.00<ref name=pulkovo/> |prop_mo_ra=0.039<ref name=edr3/> |prop_mo_dec=−4.532<ref name=edr3/> |parallax=1.5006 |p_error=0.0592 |parallax_footnote=<ref name=edr3/> |absmag_v=−1.1 (near max.)<ref name=gontcharov2011/> }} {{Starbox detail |source= |mass=4.3<ref name=starhorse/> |radius=219<ref name=tic/> |temperature=3,217<ref name=chandler2016/> |luminosity=6,025<ref name=guandalini2013/> |gravity=0.228<ref name=starhorse/> |metal_fe=−0.106<ref name=starhorse/> |rotational_velocity= |age_gyr= }} {{Starbox catalog |names={{odlist|BD=+20°1083|HD=38307|HIP=27181|HR=1977|V=Y Tau}} }} {{Starbox reference |Simbad=Y+Tauri }} {{Starbox end}}
'''Y Tauri''' is a carbon star located in the constellation Taurus. Parallax measurements by Gaia put it at a distance of approximately 2,170 light-years (670 parsecs).<ref name=edr3/>
[[File:YTauLightCurve.png|thumb|left|A visual band light curve for Y Tauri, plotted from ''ASAS'' data<ref name=ASASServer/>]] In the 19th century, Thomas William Webb and John Birmingham noted that Y Tauri might be a variable star. Thomas William Backhouse confirmed that the star's brightness varies, in 1887.<ref name="TO1887"/><ref name="AHCO1907"/> Y Tauri is a semiregular variable star. Its class is SRb, and its primary pulsation cycle lasts 241.5 days.<ref name=gcvs/> No long secondary period has been identified.<ref name=olivier2003/> It has a radius of {{solar radius|219|link=y}}, an effective surface temperature of {{val|3,217|fmt=commas|ul=K}}, and a bolometric luminosity of {{solar luminosity|4,489|link=y}}. Its mass is calculated to be {{solar mass|4.3|link=y}}.
Y Tauri is losing mass at {{val|4|e=-7|ul=solar mass}}/yr, and is surrounded by dust at a temperature of {{val|1,900|u=K|fmt=commas}}.<ref name=vdes2021/> {{clear left}}
== References == {{Reflist|refs=
<ref name=constellation>{{cite constellation|Y Tauri}}</ref>
<ref name=ASASServer>{{cite web |title=ASAS All Star Catalogue |url=http://www.astrouw.edu.pl/asas/?page=aasc |publisher=The All Sky Automated Survey |access-date=8 December 2021}}</ref>
<ref name="TO1887">{{cite journal |last1=Backhouse |first1=T. W. |title=Birmingham 121 Tauri alias Geminorum |journal=The Observatory |date=December 1887 |volume=10 |pages=429-429 |url=https://articles.adsabs.harvard.edu/pdf/1887Obs....10..429B |access-date=31 August 2025}}</ref>
<ref name="AHCO1907">{{cite journal |last1=Cannon |first1=Annie J. |title=Second catalogue of variable stars |journal=Annals of Harvard College Observatory |date=1907 |volume=55 |pages=1-94 |bibcode=1907AnHar..55....1C |url=https://articles.adsabs.harvard.edu/pdf/1907AnHar..55....1C |access-date=31 August 2025}}</ref>
<ref name=starhorse>{{cite journal |display-authors=1 |last1=Anders |first1=F. |last2=Khalatyan |first2=A. |last3=Chiappini |first3=C. |last4=Queiroz |first4=A. B. |last5=Santiago |first5=B. X. |last6=Jordi |first6=C. |last7=Girardi |first7=L. |last8=Brown |first8=A. G. A. |last9=Matijevič |first9=G. |last10=Monari |first10=G. |last11=Cantat-Gaudin |first11=T. |last12=Weiler |first12=M. |last13=Khan |first13=S. |last14=Miglio |first14=A. |last15=Carrillo |first15=I. |last16=Romero-Gómez |first16=M. |last17=Minchev |first17=I. |last18=de Jong |first18=R. S. |last19=Antoja |first19=T. |last20=Ramos |first20=P. |last21=Steinmetz |first21=M. |last22=Enke |first22=H. |title=Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18 |journal=Astronomy and Astrophysics |date=1 August 2019 |volume=628 |pages=A94 |doi=10.1051/0004-6361/201935765 |arxiv=1904.11302 |bibcode=2019A&A...628A..94A |s2cid=131780028 |issn=0004-6361}}</ref>
<ref name=edr3>{{cite Gaia EDR3|3400017749285334784}}</ref>
<ref name=gcvs>{{cite journal|bibcode=2009yCat....102025S|title=VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)|journal=VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S|volume=1|display-authors=etal|last1=Samus|first1=N. N.|last2=Durlevich|first2=O. V.|year=2009}}</ref>
<ref name=pulkovo>{{cite journal|title=Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system|author=Gontcharov, G. A.|date=2006|journal=Astronomy Letters|volume=32|issue=11|pages=759–771|bibcode=2006AstL...32..759G|doi=10.1134/S1063773706110065|arxiv=1606.08053|s2cid=119231169}}</ref>
<ref name=chandler2016>{{cite journal|bibcode=2016AJ....151...59C|doi=10.3847/0004-6256/151/3/59|arxiv=1510.05666|title=The Catalog of Earth-Like Exoplanet Survey Targets (CELESTA): A Database of Habitable Zones Around Nearby Stars|journal=The Astronomical Journal|volume=151|issue=3|pages=59|year=2016|last1=Chandler|first1=Colin Orion|last2=McDonald|first2=Iain|last3=Kane|first3=Stephen R.|s2cid=119246448 |doi-access=free }}</ref>
<ref name=tic>{{Cite journal|display-authors=1|last1=Stassun|first1=Keivan G.|last2=Oelkers|first2=Ryan J.|last3=Paegert|first3=Martin|last4=Torres|first4=Guillermo|last5=Pepper|first5=Joshua|last6=De Lee|first6=Nathan|last7=Collins|first7=Kevin|last8=Latham|first8=David W.|last9=Muirhead|first9=Philip S.|last10=Chittidi|first10=Jay|last11=Rojas-Ayala|first11=Bárbara|date=2019-10-01|title=The Revised TESS Input Catalog and Candidate Target List|bibcode=2019AJ....158..138S|journal=The Astronomical Journal|volume=158|issue=4|pages=138|doi=10.3847/1538-3881/ab3467|arxiv=1905.10694 |hdl=1721.1/124721|s2cid=166227927|issn=0004-6256|hdl-access=free |doi-access=free }}</ref>
<ref name=olivier2003>{{cite journal |doi=10.1086/345715 |title=On the Origin of Long Secondary Periods in Semiregular Variables |year=2003 |last1=Olivier |first1=E. A. |last2=Wood |first2=P. R. |journal=The Astrophysical Journal |volume=584 |issue=2 |pages=1035–1041 |bibcode=2003ApJ...584.1035O |s2cid=40373007 |doi-access=free }}</ref>
<ref name=gontcharov2011>{{cite journal |last1=Gontcharov |first1=G. A. |title=The red giant branch in the Tycho-2 catalogue |journal=Astronomy Letters |date=October 2011 |volume=37 |issue=10 |pages=707–717 |doi=10.1134/S1063773711090040 |issn=1063-7737 |bibcode=2011AstL...37..707G |arxiv=1607.00557|s2cid=119272127 }}</ref>
<ref name=vdes2021>{{cite journal |bibcode=2021MNRAS.501..491V |title=Chemical modelling of dust-gas chemistry within AGB outflows - III. Photoprocessing of the ice and return to the ISM |last1=Van De Sande |first1=M. |last2=Walsh |first2=C. |last3=Millar |first3=T. J. |journal=Monthly Notices of the Royal Astronomical Society |year=2021 |volume=501 |issue=1 |page=491 |doi=10.1093/mnras/staa3689 |doi-access=free |arxiv=2011.11563 }}</ref>
<ref name=guandalini2013>{{cite journal|bibcode=2013A&A...555A.120G|arxiv=1305.4203|title=Luminosities of carbon-rich asymptotic giant branch stars in the Milky Way|journal=Astronomy & Astrophysics|volume=555|pages=A120|last1=Guandalini|first1=R|last2=Cristallo|first2=S|year=2013|doi=10.1051/0004-6361/201321225|s2cid=54918450}}</ref>
}}
{{Stars of Taurus}}
Category:Semiregular variable stars Category:Taurus (constellation) Tauri, Y Category:Carbon stars Category:Durchmusterung objects 038307 027181 1977 Category:Asymptotic-giant-branch stars