{{Short description|Star in the constellation Taurus}} {{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=109 Tauri |x=218|y=380 }} | caption = Location of 109 Tauri (circled in red) }} {{Starbox observe | epoch = J2000 | constell = Taurus | ra = {{RA|05|19|16.60169}}<ref name=vanLeeuwen2007/> | dec = {{DEC|+22|05|47.3740}}<ref name=vanLeeuwen2007/> | appmag_v = 4.96<ref name=Anderson2012/> }} {{Starbox character | class = G8 III<ref name=Roman1952/> | b-v = {{Val|0.937|0.001}}<ref name=Anderson2012/> | u-b = | r-i = | variable = }} {{Starbox astrometry | radial_v = {{Val|+19.03|0.01}}<ref name=Jofre2015/> | prop_mo_ra = +18.91<ref name=vanLeeuwen2007/> | prop_mo_dec = −81.57<ref name=vanLeeuwen2007/> | parallax = 13.19 | p_error = 0.30 | parallax_footnote = <ref name=vanLeeuwen2007/> | absmag_v = 0.56<ref name=Anderson2012/> }} {{Starbox detail | source = <ref name=Jofre2015/> | mass = {{Val|2.47|0.08}} | radius = {{Val|8.14|0.46}} | luminosity = {{Val|60|10|12}} | gravity = {{Val|2.96|0.01}} | temperature = {{Val|5035|23|fmt=commas}} | metal_fe = {{Val|0.10|0.04}} | rotational_velocity = {{Val|1.15|0.62}} | age_myr = {{Val|600|50}} }} {{Starbox catalog | names = {{odlist | B=n Tau | F=109 Tau | BD=+21°816 | FK5=2398 | HD=34559 | HIP=24822 | HR=1739 | SAO=77097 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = 109+Tau }} {{Starbox end}}
'''109 Tauri''', or '''n Tauri''', is a single,<ref name=Eggleton2008/> yellow-hued star in the zodiac constellation of Taurus. It has an apparent visual magnitude of 4.96<ref name=Anderson2012/> and is faintly visible to the naked eye. The star has an annual parallax shift of {{Val|13.19|0.30|ul=mas}},<ref name=vanLeeuwen2007/> putting it around 247 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction of 0.24 due to interstellar dust.<ref name=Jofre2015/> It is moving further from the Sun with a heliocentric radial velocity of +19 km/s.<ref name=Jofre2015/>
This is an evolved giant star with a stellar classification of G8 III,<ref name=Roman1952/> having consumed the hydrogen at its core and moved off the main sequence. At the age of 600<ref name=Jofre2015/> million years, it has become a red clump giant, indicating that it is on the horizontal branch and is generating energy through helium fusion at its core.<ref name=Puzeras2010/> The star has an estimated 2.47 times the mass of the Sun and has expanded to around eight times the Sun's radius. It is radiating about 60 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 5,035 K.<ref name=Jofre2015/>
==References== <references> <ref name=SIMBAD>{{cite simbad | title=109 Tau | access-date=2018-03-22 }}</ref>
<ref name=vanLeeuwen2007>{{citation | title=Validation of the new Hipparcos reduction | last1=van Leeuwen | first1=F. | postscript=. | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | year=2007 | arxiv=0708.1752 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 | s2cid=18759600 }}</ref>
<ref name=Puzeras2010>{{citation | display-authors=1 | last1=Puzeras | first1=E. | last2=Tautvaišienė | first2=G. | last3=Cohen | first3=J. G. | last4=Gray | first4=D. F. | last5=Adelman | first5=S. J. | last6=Ilyin | first6=I. | last7=Chorniy | first7=Y. | title=High-resolution spectroscopic study of red clump stars in the Galaxy: iron-group elements | journal=Monthly Notices of the Royal Astronomical Society | volume=408 | issue=2 | pages=1225–1232 | date=October 2010 | doi=10.1111/j.1365-2966.2010.17195.x | doi-access=free | bibcode=2010MNRAS.408.1225P | postscript=. | arxiv=1006.3857 | s2cid=44228180 }}</ref>
<ref name=Roman1952>{{citation | title=The Spectra of the Bright Stars of Types F5-K5 | last=Roman | first=Nancy G. | postscript=. | journal=Astrophysical Journal | volume=116 | page=122 | date=July 1952 | doi=10.1086/145598 | bibcode=1952ApJ...116..122R | doi-access=free }}</ref>
<ref name=Anderson2012>{{citation | title=XHIP: An extended hipparcos compilation | last1=Anderson | first1=E. | last2=Francis | first2=Ch. | journal=Astronomy Letters | volume=38 | issue=5 | pages=331 | year=2012 | bibcode=2012AstL...38..331A | doi=10.1134/S1063773712050015 | arxiv=1108.4971 | s2cid=119257644 | postscript=. }}</ref>
<ref name=Eggleton2008>{{citation | 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 | doi=10.1111/j.1365-2966.2008.13596.x | doi-access=free | bibcode=2008MNRAS.389..869E | postscript=. | arxiv=0806.2878 | s2cid=14878976 }}</ref>
<ref name=Jofre2015>{{citation | postscript=. | title=Stellar parameters and chemical abundances of 223 evolved stars with and without planets | last1=Jofré | first1=E. | last2=Petrucci | first2=R. | last3=Saffe | first3=C. | last4=Saker | first4=L. | last5=de la Villarmois | first5=E. Artur | last6=Chavero | first6=C. | last7=Gómez | first7=M. | last8=Mauas | first8=P. J. D. | journal=Astronomy & Astrophysics | display-authors=1 | volume=574 | id=A50 | pages=46 | date=February 2015 | doi=10.1051/0004-6361/201424474 | bibcode=2015A&A...574A..50J | arxiv=1410.6422| s2cid=53666931 }}</ref> </references>
{{Stars of Taurus}}
Category:G-type giants Category:Horizontal-branch stars Category:Taurus (constellation) Tauri, n BD+21 0816 Tauri, 109 034559 024822 1739