{{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 | equinox = <!--Equinox of coordinates (defaults to epoch)--> | constell = Taurus | 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 3201 | component1 = κ<sup>1</sup> Tau | names1 = 65 Tauri, BD+21 642, HD 27934, HIP 20635, HR 1387, SAO 76601<ref name=simbad1/> | component2 = κ<sup>2</sup> Tau | names2 = 67 Tauri, BD+21 643, HD 27946, HIP 20641, HR 1388, SAO 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 in the constellation Taurus, the two components '''κ<sup>1</sup> Tauri''' and '''κ<sup>2</sup> Tauri''' both members of the Hyades open cluster. The pair are approximately 150 light years from Earth and are separated from each other by about six light years.
==System== [[File:Iades and Pleiades (32446251210).jpg|thumb|left|Pleiades and Hyades 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, κ<sup>1</sup> Tauri and κ<sup>2</sup> Tauri. κ<sup>1</sup> Tauri is a white A-type subgiant with an apparent magnitude of +4.22.<ref name="MERMILLIOD"/> It is emitting an excess of infrared radiation at a temperature indicating there is a circumstellar disk in orbit at a radius of 67 AU from the star.<ref name=apj660_2_1556/> κ<sup>2</sup> Tauri is a white A-type main sequence star with an apparent magnitude of +5.24.<ref name="MERMILLIOD"/>
Between the two bright stars is a binary star made up of two 9th magnitude stars, Kappa Tauri C and Kappa Tauri D, which are 5.5 arcseconds 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, 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 by the expedition of Arthur Eddington in Príncipe and others in Sobral, Brazil that confirmed Albert Einstein's prediction of the bending of light around the Sun from his general theory of relativity which he published in 1915.<ref name="Eddington1920"/>
==Naming== {{flowlist | * With φ, υ and χ, 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 as ''Alkalbain I'', χ as ''Alkalbain II'', these stars (κ<sup>2</sup> and κ<sup>1</sup>) are ''Alkalbain III'' and ''Alkalbain IV'', and υ as ''Alkalbain V''.<ref name=rhoads1971/> * In Chinese, {{lang|zh|天街}} ({{lang|zh-Latn|Tiān Jiē}}), meaning ''Celestial Street'', refers to an asterism consisting of κ<sup>1</sup> Tauri and ω 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|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