# Kappa Tauri

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> Markdown URL: https://mediated.wiki/source/Kappa_Tauri.md
> Source: https://en.wikipedia.org/wiki/Kappa_Tauri
> Source revision: 1352680328
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{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=κ Tauri
|x=565|y=382
}}
| caption = Location of κ Tauri (circled in red)
}}
{{Starbox observe 2s
 | epoch = [J2000.0](/source/J2000.0)
 | equinox = <!--Equinox of coordinates (defaults to epoch)-->
 | constell = [Taurus](/source/Taurus_(constellation))
 | component1 = κ<sup>1</sup> Tau
 | ra1 = {{RA|04|25|22.16505}}<ref name="van Leeuwen2007"/>
 | dec1 = {{DEC|+22|17|37.9375}}<ref name="van Leeuwen2007"/>
 | appmag_v1 = +4.22<ref name="MERMILLIOD"/>
 | component2 = κ<sup>2</sup> Tau
 | ra2 = {{RA|04|25|25.01518}}<ref name="van Leeuwen2007"/>
 | dec2 = {{DEC|+22|11|59.9876}}<ref name="van Leeuwen2007"/>
 | appmag_v2 = +5.24<ref name="MERMILLIOD"/>
}}
{{Starbox character
 | component = κ<sup>1</sup> Tau
 | class = A7IV-V<ref name=aj74_375/>
 | r-i = <!--R−I color-->
 | v-r = <!--V−R color-->
 | b-v = +0.14<ref name="MERMILLIOD"/>
 | u-b = +0.12<ref name="MERMILLIOD"/>
 | j-h = <!--J−H color-->
 | j-k = <!--J−K color-->
 | variable =
 | component2 = κ<sup>2</sup> Tau
 | class2 = A7V
 | r-i2 = <!--R−I color-->
 | v-r2 = <!--V−R color-->
 | b-v2 = +0.17<ref name="MERMILLIOD"/>
 | u-b2 = +0.09<ref name="MERMILLIOD"/>
 | j-h2 = <!--J−H color-->
 | j-k2 = <!--J−K color-->
 | variable2 =
}}
{{Starbox astrometry
 | component1 = κ<sup>1</sup> Tau
 | radial_v = +37.30<ref name=al31_11_759/>
 | prop_mo_ra = +105.10<ref name="van Leeuwen2007"/>
 | prop_mo_dec = −45.04<ref name="van Leeuwen2007"/>
 | parallax = 21.19
 | p_error = 0.21
 | parallax_footnote = <ref name="van Leeuwen2007"/>
 | absmag_v = +0.96<ref name=Eggen1998/>
 | component2 = κ<sup>2</sup> Tau
 | radial_v2 = +32.00<ref name=an328_9_889/>
 | prop_mo_ra2 = +111.97<ref name="van Leeuwen2007"/>
 | prop_mo_dec2 = −47.71<ref name="van Leeuwen2007"/>
 | parallax2 = 22.03
 | p_error2 = 0.35
 | parallax_footnote2 = <ref name="van Leeuwen2007"/>
 | absmag_v2 = +2.18<ref name=Eggen1998/>
}}
{{Starbox detail
 | component1             =   κ<sup>1</sup> Tau
 | mass                   =   <!--Mass (in solar masses)-->
 | radius                 =   2.60<ref name=apj660_2_1556/>
 | luminosity             =   33.6<ref name=mnras427_1_343/>
 | gravity                =   <!--Surface gravity (given as the base 10 logarithm expressed in cgs units)-->
 | temperature            =   9,000<ref name=apj660_2_1556/>
 | metal_fe               =   <!--Metallicity ([Fe/H] dex) -->
 | rotational_velocity    =   94<ref name=aaa463_2_671/>
 | age_gyr                =   <!--Age (in billions of years)-->
 | component2             =   κ<sup>2</sup> Tau
 | mass2                  =   <!--Mass (in solar masses)-->
 | radius2                =   <!--Radius (in solar radii)-->
 | luminosity2            =   11.8<ref name=mnras427_1_343/>
 | gravity2               =   <!--Surface gravity (given as the base 10 logarithm expressed in cgs units)-->
 | temperature2           =   7,400<ref name=mnras427_1_343/>
 | metal2_fe              =   <!--Metallicity ([Fe/H] dex) -->
 | rotational_velocity2   =   191<ref name=aaa463_2_671/>
 | age_gyr2               =   <!--Age (in billions of years)-->
}}
{{Starbox catalog
 | names      = κ Tau, [ADS](/source/Star_catalogue)&nbsp;3201
 | component1 = κ<sup>1</sup> Tau
 | names1     = 65&nbsp;Tauri, [BD](/source/Star_catalogue)+21&nbsp;642, [HD](/source/Henry_Draper_Catalogue)&nbsp;27934, [HIP](/source/Hipparcos_catalogue)&nbsp;20635, [HR](/source/Star_catalogue)&nbsp;1387, [SAO](/source/Star_catalogue)&nbsp;76601<ref name=simbad1/>
 | component2 = κ<sup>2</sup> Tau
 | names2     = 67 Tauri, BD+21&nbsp;643, HD&nbsp;27946, HIP&nbsp;20641, HR&nbsp;1388, SAO&nbsp;76602<ref name=simbad2/>
}}
{{Starbox reference
 | Simbad = kap01+Tau | sn=κ<sup>1</sup> Tau
 | Simbad2 = kap02+Tau | sn2=κ<sup>2</sup> Tau
}}
{{Starbox end}}
'''Kappa Tauri''' (κ Tau, κ Tauri) is a [double star](/source/double_star) in the [constellation](/source/constellation) [Taurus](/source/Taurus_(constellation)), the two components '''κ<sup>1</sup> Tauri''' and '''κ<sup>2</sup> Tauri''' both members of the [Hyades](/source/Hyades_(star_cluster)) [open cluster](/source/star_cluster). The pair are approximately 150 [light years](/source/light_years) from [Earth](/source/Earth) and are separated from each other by about six light years.

==System==
[[File:Iades and Pleiades (32446251210).jpg|thumb|left|[Pleiades](/source/Pleiades) and [Hyades](/source/Hyades_cluster) with κ Tauri as the very close pair at lower centre (north is approximately to the left)]]
The system is dominated by a visual [double star](/source/double_star), κ<sup>1</sup> Tauri and κ<sup>2</sup> Tauri.  κ<sup>1</sup> Tauri is a white [A-type](/source/stellar_classification) [subgiant](/source/subgiant) with an [apparent magnitude](/source/apparent_magnitude) of +4.22.<ref name="MERMILLIOD"/> It is emitting an [excess of infrared](/source/Infrared_excess) radiation at a temperature indicating there is a [circumstellar disk](/source/circumstellar_disk) in orbit at a radius of 67&nbsp;[AU](/source/Astronomical_unit) from the star.<ref name=apj660_2_1556/> κ<sup>2</sup> Tauri is a white [A-type main sequence star](/source/A-type_main_sequence_star) with an [apparent magnitude](/source/apparent_magnitude) of +5.24.<ref name="MERMILLIOD"/>

Between the two bright stars is a [binary star](/source/binary_star) made up of two 9th magnitude stars, Kappa Tauri C and Kappa Tauri D, which are 5.5 [arcsecond](/source/arcsecond)s from each other (as of 2013) and 175.1 arcseconds from κ<sup>1</sup> Tau. Two more 12th magnitude companions fill out the visual group: Kappa Tauri E, which is 145 arcseconds from κ<sup>1</sup> Tau, and Kappa Tauri F, 108.5 arcseconds away from κ<sup>2</sup> Tau.<ref name=WDSC2014/>

The bright pair are both members of the [Hyades star cluster](/source/Hyades_star_cluster), while the fainter stars are all much more distant background stars.<ref name=aj84_1770/>

==Test of General Relativity==
thumb|left|upright|One of the 1919 eclipse negatives, with κ<sup>1</sup> and κ<sup>2</sup> Tauri marked near the centre of the image
Kappa Tauri was photographed during the [solar eclipse of May 29, 1919](/source/solar_eclipse_of_May_29%2C_1919) by the expedition of [Arthur Eddington](/source/Arthur_Eddington) in [Príncipe](/source/Pr%C3%ADncipe) and others in [Sobral, Brazil](/source/Sobral%2C_Cear%C3%A1) that [confirmed](/source/tests_of_general_relativity) [Albert Einstein](/source/Albert_Einstein)'s prediction of the [bending of light](/source/gravitational_lens) around the [Sun](/source/Sun) from his [general theory of relativity](/source/general_relativity) which he published in 1915.<ref name="Eddington1920"/>

==Naming==
{{flowlist |
* With [φ](/source/Phi_Tauri), [υ](/source/Upsilon_Tauri) and [χ](/source/Chi_Tauri), it composed the Arabic were the Arabs' '''Al Kalbain''', the Two Dogs.<ref name="allen1899"/> According to the catalogue of stars in the ''Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars'', ''Al Kalbain'' were the title for five stars: [φ](/source/Phi_Tauri) as ''Alkalbain I'', [χ](/source/Chi_Tauri) as ''Alkalbain II'', these stars (κ<sup>2</sup> and κ<sup>1</sup>) are ''Alkalbain III'' and ''Alkalbain IV'', and [υ](/source/Upsilon_Tauri) as ''Alkalbain V''.<ref name=rhoads1971/>
* In [Chinese](/source/Chinese_language), {{lang|zh|天街}} ({{lang|zh-Latn|Tiān Jiē}}), meaning ''[Celestial Street](/source/Net_(Chinese_constellation))'', refers to an asterism consisting of κ<sup>1</sup> Tauri and [ω Tauri](/source/Omega_Tauri). Consequently, κ<sup>1</sup> Tauri itself is known as {{lang|zh|天街一}} ({{lang|zh-Latn|Tiān Jiē yī}}, {{langx|en|the First Star Star of Celestial Street}}).<ref>{{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0605/ap060523.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 23 日] {{Webarchive|url=https://web.archive.org/web/20140226175900/http://aeea.nmns.edu.tw/2006/0605/ap060523.html |date=2014-02-26 }}</ref>
}}
{{clear left}}
==References==
<references>
<ref name="van Leeuwen2007">{{citation
 | last1=van Leeuwen | first1=F.
 | title=Validation of the new Hipparcos reduction
 | journal=Astronomy and Astrophysics
 | volume=474 | issue=2 | pages=653–664 | year=2007
 | bibcode=2007A&A...474..653V
 | doi=10.1051/0004-6361:20078357
 | arxiv=0708.1752
 | s2cid=18759600
 | postscript=.
}}</ref>

<ref name=al31_11_759>{{citation
 | last1=Gontcharov | first1=G. A.
 | title=Pulkovo Compilation of Radial Velocities for 35,495 Hipparcos stars in a common system
 | journal=Astronomy Letters
 | volume=32 | issue=11 | pages=759–771 | date=November 2006
 | doi=10.1134/S1063773706110065
 | bibcode=2006AstL...32..759G
 | postscript=.
|arxiv = 1606.08053 | s2cid=119231169
 }}</ref>

<ref name=simbad1>{{cite simbad
 | title=* kap01 Tau
 | access-date=2015-11-05
 }}</ref>

<ref name=simbad2>{{cite simbad
 | title=* kap02 Tau
 | access-date=2015-11-05
 }}</ref>

<ref name=an328_9_889>{{citation
 | display-authors=1
 | last1=Kharchenko | first1=N. V.
 | last2=Scholz | first2=R.-D.
 | last3=Piskunov | first3=A. E.
 | last4=Röser | first4=S.
 | last5=Schilbach | first5=E.
 | title=Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ˜55000 stars and mean radial velocities of 516 Galactic open clusters and associations
 | journal=Astronomische Nachrichten
 | volume=328 | issue=9 | pages=889–896 | year=2007
 | doi=10.1002/asna.200710776
 | bibcode=2007AN....328..889K
 | arxiv=0705.0878
 | s2cid=119323941 | postscript=.
}}</ref>

<ref name="MERMILLIOD">{{citation
 | last1=Mermilliod | first1=J.-C.
 | title=Compilation of Eggen's UBV data, transformed to UBV (unpublished)
 | journal=Catalogue of Eggen's UBV Data. SIMBAD
 | date=1986 | bibcode=1986EgUBV........0M
 | postscript=.
}}</ref>

<ref name=aj74_375>{{citation
 | display-authors=1
 | last1=Cowley | first1=A.
 | last2=Cowley | first2=C.
 | last3=Jaschek | first3=M.
 | last4=Jaschek | first4=C.
 | title=A study of the bright A stars. I. A catalogue of spectral classifications
 | journal=Astronomical Journal
 | volume=74 | pages=375–406 | date=April 1969
 | doi=10.1086/110819
 | bibcode=1969AJ.....74..375C
}}</ref>

<ref name=aaa463_2_671>{{citation
 | display-authors=1
 | last1=Royer | first1=F.
 | last2=Zorec | first2=J.
 | last3=Gómez | first3=A. E.
 | title=Rotational velocities of A-type stars. III. Velocity distributions
 | journal=Astronomy and Astrophysics
 | volume=463 | issue=2 | pages=671–682 | date=February 2007
 | doi=10.1051/0004-6361:20065224
 | bibcode=2007A&A...463..671R
 | arxiv=astro-ph/0610785
 | s2cid=18475298 | postscript=.
}}</ref>

<ref name=apj660_2_1556>{{citation
 | display-authors=1
 | last1=Rhee | first1=Joseph H.
 | last2=Song | first2=Inseok
 | last3=Zuckerman | first3=B.
 | last4=McElwain | first4=Michael
 | title=Characterization of Dusty Debris Disks: The IRAS and Hipparcos Catalogs
 | journal=The Astrophysical Journal
 | volume=660 | issue=2 | pages=1556–1571
 | date=May 2007
 | doi=10.1086/509912
 | bibcode=2007ApJ...660.1556R
 | postscript=.
|arxiv = astro-ph/0609555 | s2cid=11879505 }}</ref>

<ref name=mnras427_1_343>{{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
 | doi-access=free | s2cid=118665352 | postscript=.
}}</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
 | year=2014 | bibcode=2001AJ....122.3466M
 | url=http://vizier.u-strasbg.fr/viz-bin/VizieR-S?WDS%20J04254%2b2218A
 | access-date=2015-11-08
|doi = 10.1086/323920 | volume=122 | issue=6 | journal=The Astronomical Journal | pages=3466–3471| doi-access=free}}</ref>

<ref name=aj84_1770>{{citation
 | last1=Horan | first1=S.
 | title=A photometric survey of the Hyades for Delta Scuti variables
 | journal=Astronomical Journal
 | volume=84 | pages=1770–1774
 | date=November 1979
 | doi=10.1086/112607
 | bibcode=1979AJ.....84.1770H
| doi-access=free
 }}</ref>

<ref name="Eddington1920">{{cite journal|last=Dyson|author2=Eddington, A.S.|author3=Davidson, C.R. |date=1920 |title=A Determination of the Deflection of Light by the Sun's Gravitational Field, from Observations Made at the Solar eclipse of May 29, 1919|journal= [Phil. Trans. Roy. Soc. A](/source/Philosophical_Transactions_of_the_Royal_Society_A)|volume=220|issue=571–581|pages= 291–333|bibcode=1920RSPTA.220..291D|doi=10.1098/rsta.1920.0009|first =F.W.|url=https://zenodo.org/record/1432106|doi-access=free}}</ref>

<ref name=Eggen1998>{{citation
 | title=The Age Range of Hyades Stars
 | last1=Eggen | first1=Olin J. | postscript=.
 | journal=The Astronomical Journal
 | volume=116 | issue=1 | pages=284–292 | date=July 1998
 | doi=10.1086/300413 | bibcode=1998AJ....116..284E | doi-access=free }}</ref>

<ref name="allen1899">{{citation | title=Star-Names and Their Meanings | last=Allen | first=Richard Hinckley | author-link=Richard Hinckley Allen | date=1899 | publisher=G. E. Stechert | location=New York | page=413 }}</ref>

<ref name=rhoads1971>{{citation | url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19720005197_1972005197.pdf | first1=Jack W. | last1=Rhoads | title=Technical Memorandum 33-507-A Reduced Star Catalog Containing 537 Named Stars | publisher=Jet Propulsion Laboratory, California Institute of Technology | date=November 15, 1971 | postscript=. }}</ref>
</references>

{{Stars of Taurus}}

Tauri, Kappa
Category:Taurus (constellation)
6
Category:A-type subgiants
Category:A-type main-sequence stars
Category:Hyades (star cluster)
Tauri, 65
027934/46
020635/41
1387/8
BD+21 0642
Category:Double stars

---
Adapted from the Wikipedia article [Kappa Tauri](https://en.wikipedia.org/wiki/Kappa_Tauri) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Kappa_Tauri?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.