View source for Astronomy:Epsilon Telescopii

{{Short description|Star in the constellation Telescopus}}
{{Starbox begin
 | name = [[Astronomy:Bayer designation|ε Telescopii]]
}}
{{Starbox observe
 | epoch = [[Astronomy:J2000.0|J2000.0]] ([[Astronomy:International Celestial Reference System|ICRS]])
 | constell = [[Astronomy:Telescopium|Telescopium]]
 | ra = {{RA|18|11|13.7612}}<ref name = EDR3/>
 | dec = {{DEC|−45|57|15.8824}}<ref name = EDR3/>
 | appmag_v = 4.50{{±|0.01}}<ref name = Tycho2000/>
}}
{{Starbox character
 | class = K0 III<ref name=houk1978/>
 | b-v = +1.01<ref name=Johnson1966/>
 | u-b = +0.78<ref name=Johnson1966/>
 | r-i = 
 | variable = 
}}
{{Starbox astrometry
 | radial_v = −26.3{{±|0.8}}<ref name = Gontcharov2006/>
 | prop_mo_ra = −18.837
 | prop_mo_dec = −38.102
 | parallax = 8.0405
 | p_error = 0.321
 | parallax_footnote = <ref name = EDR3/>
 | pm_footnote = <ref name = EDR3/>
 | absmag_v = −1.00<ref name=Anderson2012/>
}}
{{Starbox detail
 | source = 
 | mass = 
 | radius = 
 | luminosity = 293<ref name=Mcdonald2012/>
 | temperature = {{Val|4996|42|fmt=commas}}<ref name=Alves2015/>
 | gravity = {{Val|2.32|0.12}}<ref name=Alves2015/>
 | metal_fe = {{Val|−0.07|0.04}}<ref name=Alves2015/>
 | rotational_velocity = 
 | age_gyr = 
}}
{{Starbox catalog
 | names = {{odlist | B=ε Tel | CD=−45° 12251 | FK5=1473 | HD=166063 | HIP=89112 | HR=6783 | SAO=228777 }}<ref name=SIMBAD/>
}}
{{Starbox reference|Simbad=eps+Tel}}
{{Starbox end}}
'''Epsilon Telescopii''', [[Social:Latinisation of names|Latinized]] from ε Telescopii, is a solitary,<ref name=Eggleton2008/> orange-hued [[Astronomy:Star|star]] in the southern [[Astronomy:Constellation|constellation]] of [[Astronomy:Telescopium|Telescopium]]. It is visible to the naked eye with an [[Astronomy:Apparent visual magnitude|apparent visual magnitude]] of +4.53.<ref name=Johnson1966/> Based upon an annual [[Astronomy:Stellar parallax|parallax shift]] of 7.80&nbsp;mas as seen from Earth,<ref name = EDR3/> it is located roughly 410&nbsp;[[Light year|light year]]s from the [[Astronomy:Sun|Sun]], give or take 20 light years.

This an [[Astronomy:Stellar evolution|evolved]] [[Astronomy:Stellar classification|K-type]] [[Astronomy:Giant star|giant]] with a [[Astronomy:Stellar classification|stellar classification]] of K0&nbsp;III.<ref name=houk1978/> It displays an [[Astronomy:Infrared excess|infrared excess]], suggesting the presence of an orbiting disk of dust.<ref name=Zuckerman1995/> The star is radiating 293<ref name=Mcdonald2012/> times the [[Astronomy:Solar luminosity|Sun's luminosity]] from its [[Astronomy:Photosphere|photosphere]] at an [[Astronomy:Effective temperature|effective temperature]] of 4,996&nbsp;K.<ref name=Alves2015/> It has a 13th magnitude optical companion at an angular separation of 16.30&nbsp;[[Arcsecond|arcsecond]]s along a [[Astronomy:Position angle|position angle]] of 233°, as of 2000.<ref name=WDSC2014/>

==References==
{{reflist|refs=

<ref name = EDR3>{{Cite Gaia EDR3|6719649408908407680}}</ref>

<ref name = Tycho2000>{{cite journal |last1=Høg |first1=E. |last2=Fabricius |first2=C. |last3=Makarov |first3=V. V. |last4=Urban |first4=S. |last5=Corbin |first5=T. |last6=Wycoff |first6=G. |last7=Bastian |first7=U. |last8=Schwekendiek |first8=P. |last9=Wicenec |first9=A. |title=The Tycho-2 catalogue of the 2.5 million brightest stars |journal=Astronomy and Astrophysics |date=March 2000 |volume=355 |pages=L27–L30 |bibcode=2000A&A...355L..27H |issn=0004-6361 }}</ref>

<ref name=WDSC2014>{{citation
 | display-authors=1 | last1=Mason | first1=B. D.
 | last2=Wycoff | first2=G. L. | last3=Hartkopf | first3=W. I.
 | last4=Douglass | first4=G. G. | last5=Worley | first5=C. E.
 | title=The Washington Visual Double Star Catalog
 | journal=The Astronomical Journal | year=2014 | volume=122 | issue=6 | page=3466 | bibcode=2001AJ....122.3466M
 | url=http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/wds
 | accessdate=2015-07-22 | doi=10.1086/323920 | doi-access=free }}</ref>

<ref name = Gontcharov2006>{{cite journal |last1=Gontcharov |first1=G. A. |title=Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system |journal=Astronomy Letters |date=November 2006 |volume=32 |issue=11 |pages=759–771 |doi=10.1134/S1063773706110065 |issn=1063-7737 |bibcode=2006AstL...32..759G |arxiv=1606.08053|s2cid=119231169 }}</ref>

<ref name=Mcdonald2012>{{citation
 | display-authors=1 | last1=McDonald | first1=I.
 | last2=Zijlstra | first2=A. A. | last3=Boyer | first3=M. L.
 | title=Fundamental Parameters and Infrared Excesses of Hipparcos Stars
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=427 | issue=1 | pages=343–57 | date=2012
 | bibcode=2012MNRAS.427..343M | arxiv=1208.2037
 | doi=10.1111/j.1365-2966.2012.21873.x | s2cid=118665352 | postscript=. }}</ref>

<ref name=Zuckerman1995>{{citation
 | title=Luminosity Class III Stars with Excess Far-Infrared Emission
 |display-authors=1 | last1=Zuckerman | first1=B.
 | last2=Kim | first2=Sungsoo S. | last3=Liu | first3=T.
 | journal=Astrophysical Journal Letters
 | volume=446 | page=L79 | date=June 1995 | postscript=. 
 | doi=10.1086/187935 | bibcode=1995ApJ...446L..79Z | doi-access=free }}</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=[[Organization:Monthly Notices of the Royal Astronomical Society|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 | bibcode=2008MNRAS.389..869E
 | arxiv=0806.2878 | s2cid=14878976 | postscript=. }}</ref>

<ref name=Alves2015>{{citation
 | display-authors=1 | last1=Alves | first1=S.
 | last2=Benamati | first2=L. | last3=Santos | first3=N. C.
 | last4=Adibekyan | first4=V. Zh. | last5=Sousa | first5=S. G.
 | last6=Israelian | first6=G. | last7=De Medeiros | first7=J. R.
 | last8=Lovis | first8=C. | last9=Udry | first9=S.
 | title=Determination of the spectroscopic stellar parameters for 257 field giant stars
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=448 | issue=3 | pages=2749–2765 | date=April 2015
 | doi=10.1093/mnras/stv189 | bibcode=2015MNRAS.448.2749A
 | arxiv=1503.02556 | postscript=. }} Per the comments in the paper, this lists the TS13 data.</ref>

<ref name=houk1978>{{citation
 | last1=Houk | first1=Nancy | postscript=.
 | title=Michigan catalogue of two-dimensional spectral types for the HD stars
 | volume=2 | publication-place=Ann Arbor
 | publisher=Dept. of Astronomy, University of Michigan
 | year=1978 | bibcode=1978mcts.book.....H }}</ref>

<ref name=Johnson1966>{{citation | display-authors=1
 | last1=Johnson | first1=H. L. | last2=Iriarte | first2=B.
 | last3=Mitchell | first3=R. I. | last4=Wisniewskj | first4=W. Z.
 | title=UBVRIJKL photometry of the bright stars
 | journal=Communications of the Lunar and Planetary Laboratory
 | volume=4 | issue=99 | year=1966
 | page=99 | bibcode=1966CoLPL...4...99J | postscript=. }}</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=SIMBAD>{{cite simbad
 | title=* eps Tel
 | accessdate=2017-06-07 | postscript=. }}</ref>

}}

{{Stars of Telescopium|state=collapsed}}

{{DEFAULTSORT:Epsilon Telescopii}}
[[Category:K-type giants]]
[[Category:Bayer objects|Telescopii, Epsilon]]
[[Category:Henry Draper Catalogue objects|166063]]
[[Category:Hipparcos objects|089912]]
[[Category:Bright Star Catalogue objects|6783]]
[[Category:Durchmusterung objects]]

{{Sourceattribution|Epsilon Telescopii}}