View source for KS Persei

{{Starbox begin}}
{{Starbox image
| image = [[Image:KSPerLightCurve.png|250px]]
| caption = A [[light curve]] for KS Persei, plotted from ''[[Hipparcos]]'' data<ref name=CDS/>
}}
{{Starbox observe
 | epoch       = J2000.0
 | constell    = [[Perseus (constellation)|Perseus]]
 | ra          = {{RA|04|48|53.348}}<ref name=GaiaEDR3/>
 | dec         = {{DEC|43|16|32.09}}<ref name=GaiaEDR3/>
 | appmag_v    = 7.70<ref name=Anderson_Francis_2012/>
}}
{{Starbox character
 | type        = 
 | class       = {{nowrap|A5Iap}}<ref name=Boulon1959/> + B2/3Ia/Ib<ref name=Drilling_Schonberner_1982/>
 | b-v         = 0.423{{±|0.019}}<ref name=Anderson_Francis_2012/>
 | u-b         = 
 | variable    = [[Semiregular variable star|Semiregular]]<ref name=Samus_et_al_2017/>
}}
{{Starbox astrometry
 | radial_v    = 
 | prop_mo_ra  = 1.600
 | prop_mo_dec = −1.781
 | pm_footnote = <ref name=GaiaEDR3/>
 | parallax    = 0.1004
 | p_error     = 0.0414
 | parallax_footnote = <ref name=GaiaEDR3/>
 | dist_ly     = < 3,200
 | dist_pc     = < 1,000<ref name=Kipper_Klochkova_2008/>
 | absmag_v    = −3.3<ref name=Kipper_Klochkova_2008/>
}}
{{Starbox orbit
 | reference   = <ref name=Heard1962/>
 | primary     = <!--Primary name -->
 | name        = <!--Companion name-->
 | period      = <!--(P) Period (in years)-->
 | period_unitless = {{val|360.47|1.07|u=days}}
 | axis        = <!--(a) Semimajor axis (in arcseconds)-->
 | axis_unitless = ≥{{cvt|243|±|8|Gm|AU}}
 | eccentricity = 0.28{{±|0.03}}
 | inclination = <!--(i) Inclination (in degrees)-->
 | node        = <!--(Ω) Longitude of node (in degrees)-->
 | periastron  = {{val|2435141.74|5.06|ul=JD|fmt=commas}}
 | periarg     = 268.4{{±|4.8}}
 | periarg_primary = <!--(ω) Argument of periastron (in degrees), primary -->
 | k1          = 51.4{{±|1.6}}
 | k2          = <!-- Velocity semi-amplitude (secondary in SB2), in km/s -->
}}
{{Starbox detail
 | component1  = Supergiant
 | mass        = 1.0 (assumed)<ref name=Parthasarathy_et_al_2007/>
 | radius      = 
 | luminosity  = 2,000<ref name=Kipper_Klochkova_2008/>
 | gravity     = 2.0{{±|0.5}}<ref name=Kipper_Klochkova_2008/>
 | temperature = 9,500{{±|300}}<ref name=Kipper_Klochkova_2008/>
 | metal_fe    = −0.73{{±|0.10}}<ref name=Gáspár_et_al_2016/>
 | rotation    = 
 | rotational_velocity = 
 | age_myr     = 
 | component2  = Companion
 | mass2       = 5 (times the primary mass)<ref name=Parthasarathy_et_al_2007/>
 | temperature2= 12,500<ref name=Parthasarathy_et_al_2007/>
}}
{{Starbox catalog
 | names = {{odlist | name=Bidelman's Star | V=KS Per | HD=30353 | BD=+43 1069 | HIP=22365 | SAO=39773 | AG=+43 500 }}<ref name=SIMBAD/>
}}
{{Starbox reference
 | Simbad = KS+Per
}}
{{Starbox end}}

'''KS Persei''' is a [[binary system]] in the [[celestial equator|equatorial]] [[constellation]] of [[Perseus (constellation)|Perseus]]. It is sometimes known as Bidelman's Star, named after [[William P. Bidelman]].<ref name=SIMBAD/><ref name=Anderson_Francis_2012/> The star is invisible to the naked eye with a mean [[apparent visual magnitude]] of 7.70.<ref name=Anderson_Francis_2012/> As of 2018, the structure and evolutionary history of this system remain uncertain, although some form of mass transfer is likely to have occurred to explain the observed properties.<ref name=Hall_Jeffery_2018/>

The peculiar nature of the [[stellar spectrum|spectra]] for this star was noted in the ''[[Henry Draper Catalogue]]'' and was the subject of a study by W. P. Bidelman published in 1950. He found extremely weak [[absorption line|lines]] of hydrogen, similar to those for [[Upsilon Sagittarii]] but at a lower temperature. The data strongly suggested the star has an abnormally low abundance of hydrogen in the [[stellar atmosphere]]. Bidelman noted that the [[radial velocity]] of the star is variable, demonstrating that it has an unseen companion.<ref name=Bidelman1950/> Preliminary [[orbital elements]] for this single-lined [[spectroscopic binary]] were published in 1955 by [[John Frederick Heard|J. F. Heard]] and [[Olga Boshko|O. Boshko]], giving an [[orbital period]] of 359.7&nbsp;days and with [[orbital eccentricity|eccentricity]] of 0.27. They found a large [[Binary mass function|mass function]] of 4.5, suggesting that the supergiant has lost mass and the companion is relatively massive.<ref name=Heard_Boshko_1955/>  The mass function was revised to 3.6{{±|0.4}} in 1988, suggesting the secondary is five times more massive than the primary.<ref name=Kipper_Klochkova_2008/>  Although the [[Gaia (spacecraft)|Gaia]] parallax is small (and the [[Hipparcos]] parallax is negative), KS Persei is thought to be less than {{val|1,000|ul=pc|fmt=commas}} away.  Older studies have suggested distances up to {{val|3,900|u=pc|fmt=commas}}.<ref name=Kipper_Klochkova_2008/>

An analysis by [[George Wallerstein|G. Wallerstein]] and associates in 1967 showed that nitrogen is the second most abundant element in the primary, likely as a result of [[CNO cycle|carbon cycling]].<ref name=Wallerstein_et_al_1967/> [[Gáspár Á. Bakos|G. A. Bakos]] attempted to [[Photometry (astronomy)|photometrically]] detect an eclipse but was unsuccessful. However, he did tentatively detect semiregular variation with a period of ~30 days and an amplitude of 0.1 magnitude. This variability was confirmed by [[Keith Morrison (astronomer)|K. Morrison]] and [[Graham Percy Henry Willingale|G. P. H. Willingale]] in 1987, and they discovered an additional five day cycle.<ref name=Morrison_Willingale_1987/> In 1982, [[John Scott Drilling|J. S. Drilling]] and [[Detlef Schönberner|D. Schönberner]] detected a hot companion from spectra collected by the [[International Ultraviolet Explorer]].<ref name=Drilling_Schonberner_1982/> The system is an infrared source, and models of the infrared flux suggest it is being emitted by circumstellar dust heated to {{val|1100|u=K|fmt=commas}}.<ref name=Kipper_Klochkova_2008/> It is possible that the companion is obscured by dust.<ref name=Parthasarathy_et_al_2007/>

== References ==
{{reflist|refs=

<ref name=CDS>{{cite journal
 | title=The HIPPARCOS and TYCHO catalogues | author=EAS
 | journal=Astrometric and Photometric Star Catalogues Derived from the ESA Hipparcos Space Astrometry Mission
 | publication-place=Noordwijk, Netherlands | publisher=ESA Publications Division
 | year=1997 | series=ESA SP Series | volume=1200 | isbn=9290923997
 | bibcode=1997HIP...C......0E
 | url=https://cdsarc.cds.unistra.fr/viz-bin/ftp-index?/ftp/cats/more/HIP/cdroms/cats
 | access-date=15 October 2022}}</ref>

<ref name=SIMBAD>{{cite simbad
 | title=KS Per | access-date=2022-03-26 | postscript=. | mode=cs2 }}</ref>

<ref name=GaiaEDR3>{{Cite Gaia EDR3|204531088580182016}}</ref>

<ref name=Boulon1959>{{citation | postscript=. |bibcode=1959JO.....42..149B |title=La mesure des vitesses radiales au prisme objectif - X - 4e liste de vitesses radiales déterminées au prisme objectif à vision directe |last1=Boulon |first1=J. |last2=Fehrenbach |first2=C. |last3=Duflot |first3=A. |last4=Rebeirot |first4=E. |last5=Petit |first5=M. |journal=Journal des Observateurs |year=1959 |volume=42 |page=149 }}</ref>

<ref name=Samus_et_al_2017>{{citation | postscript=.
 | title=General catalogue of variable stars | version=GCVS 5.1
 | last1=Samus' | first1=N. N | last2=Kazarovets | first2=E. V
 | last3=Durlevich | first3=O. V | last4=Kireeva | first4=N. N
 | last5=Pastukhova | first5=E. N | journal=Astronomy Reports
 | display-authors=1 | volume=61 | issue=1 | pages=80 | year=2017
 | bibcode=2017ARep...61...80S | s2cid=125853869
 | doi=10.1134/S1063772917010085 }}</ref>

<ref name=Heard1962>{{citation | postscript=.
 | title=The spectroscopic orbit of Bidelman's peculiar star H.D. 30353
 | last=Heard | first=John Frederick
 | journal=Publications of the David Dunlap Observatory
 | publisher=University of Toronto Press
 | publication-place=Toronto, Canada 
 | volume=2 | issue=9 | date=1962 | pages=269–277
 | bibcode=1962PDDO....2..269H }}</ref>

<ref name=Bidelman1950>{{citation | postscript=.
 | title=The Peculiar Star HD 30353
 | last=Bidelman | first=William P.
 | journal=Astrophysical Journal
 | volume=111 | page=333 | date=March 1950
 | doi=10.1086/145268 | bibcode=1950ApJ...111..333B }}</ref>

<ref name=Anderson_Francis_2012>{{citation | postscript=.
 | last1=Anderson | first1=E. | last2=Francis | first2=Ch.
 | title=XHIP: An extended hipparcos compilation
 | journal=Astronomy Letters
 | volume=38 | issue=5 | pages=331 | year=2012
 | bibcode=2012AstL...38..331A | arxiv=1108.4971
 | doi=10.1134/S1063773712050015 | s2cid=119257644 }}</ref>

<ref name=Kipper_Klochkova_2008>{{citation | postscript=.
 | title=Improved Parameters of the Hydrogen-Deficient Binary Star KS Per
 | last1=Kipper | first1=Tõnu | last2=Klochkova | first2=Valentina G.
 | journal=Baltic Astronomy
 | volume=17 | pages=195–207 | date=2008
 | arxiv=0806.2709 | bibcode=2008BaltA..17..195K }}</ref>

<ref name=Gáspár_et_al_2016>{{citation
 | display-authors=1 | last1=Gáspár | first1=András
 | last2=Rieke | first2=George H. | last3=Ballering | first3=Nicholas
 | title=The Correlation between Metallicity and Debris Disk Mass
 | journal=The Astrophysical Journal | postscript=.
 | volume=826 | issue=2 | pages=171 | year=2016
 | bibcode=2016ApJ...826..171G | arxiv=1604.07403
 | doi=10.3847/0004-637X/826/2/171 | s2cid=119241004 | doi-access=free }}</ref>

<ref name=Parthasarathy_et_al_2007>{{citation | postscript=.
 | title=Progenitors of type Ia supernovae: Binary stars with white dwarf companions
 | last1=Parthasarathy | first1=M. | last2=Branch | first2=David
 | last3=Jeffery | first3=David J. | last4=Baron | first4=E.
 | display-authors=1 | journal=New Astronomy Reviews
 | volume=51 | issue=5–6 | pages=524–538
 | date=June 2007 | doi=10.1016/j.newar.2007.03.001
 | arxiv=astro-ph/0703415 | bibcode=2007NewAR..51..524P | s2cid=18539861
 }}</ref>

<ref name=Heard_Boshko_1955>{{citation | postscript=.
 | title=The orbital elements of the hydrogen-poor spectroscopic binary HD 30353
 | last1=Heard | first1=J. F. | last2=Boshko | first2=O.
 | journal=Astronomical Journal
 | volume=60 | page=162 | date=June 1955
 | doi=10.1086/107194 | bibcode=1955AJ.....60..162H }}</ref>

<ref name=Wallerstein_et_al_1967>{{citation | postscript=.
 | title=Abundances of the Light Elements in the Hydrogen-Poor Star HD 30353
 | display-authors=1 | last1=Wallerstein | first1=George
 | last2=Greene | first2=Thomas F. | last3=Tomley | first3=Leslie J.
 | journal=Astrophysical Journal
 | volume=150 | page=245 | date=October 1967
 | doi=10.1086/149326 | bibcode=1967ApJ...150..245W }}</ref>

<ref name=Drilling_Schonberner_1982>{{citation | postscript=.
 | title=The hot component of KS Per (HD 30353)
 | last1=Drilling | first1=J. S. | last2=Schonberner | first2=D.
 | journal=Astronomy and Astrophysics
 | volume=113 | pages=L22–L23 | date=September 1982
 | bibcode=1982A&A...113L..22D }}</ref>

<ref name=Morrison_Willingale_1987>{{citation | postscript=.
 | title=The photometric variability of the extremely hydrogen-deficient stars KS Persei and LSII +33 5
 | last1=Morrison | first1=K. | last2=Willingale | first2=G. P. H.
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=228 | pages=819–825 | date=October 1987
 | issue=4
 | doi=10.1093/mnras/228.4.819 | bibcode=1987MNRAS.228..819M | doi-access=free }}</ref>

<ref name=Hall_Jeffery_2018>{{citation | postscript=.
 | title=The positive binding energy envelopes of low-mass helium stars
 | last1=Hall | first1=Philip D. | last2=Jeffery | first2=C.
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=475 | issue=3 | pages=3889–3895 | date=April 2018
 | doi=10.1093/mnras/sty055 | doi-access=free
 | bibcode=2018MNRAS.475.3889H }}</ref>

}}

==Further reading==
{{Div col|small=yes}}
*{{citation | postscript=.
 | title=The ultraviolet spectrum of the hydrogen-poor binary HD 30353
 | display-authors=1 | last1=Parthasarathy | first1=M.
 | last2=Hack | first2=M. | last3=Tektunali | first3=G.
 | journal=Astronomy and Astrophysics
 | volume=230 | pages=136–144 | date=April 1990
 | bibcode=1990A&A...230..136P }}
*{{citation | postscript=.
 | title=The ultraviolet spectrum of the binary system KS Persei (HD 30353)
 | last=Tektunali | first=H. Gokmen
 | journal=Astrophysics and Space Science
 | volume=158 | issue=2 | pages=223–228 | date=August 1989
 | doi=10.1007/BF00639726 | bibcode=1989Ap&SS.158..223T | s2cid=123525338
 }}
*{{citation | postscript=.
 | title=Investigations on binaries with more massive invisible components. I.The H-deficient system KS Persei
 | display-authors=1 | last1=Margoni | first1=R.
 | last2=Stagni | first2=R. | last3=Mammano | first3=A.
 | journal=Astronomy and Astrophysics Supplement Series
 | volume=75 | pages=157–162 | date=October 1988
 | bibcode=1988A&AS...75..157M }}
*{{citation | postscript=.
 | title=Deplacement vers le violet de la raie d'absorption H alpha de l'etoile HD 30353 depourvue d'hydrogene
 | last=Nariai | first=K.
 | journal=Publications of the Astronomical Society of Japan
 | volume=24 | page=495 | date=1972
 | bibcode=1972PASJ...24..495N }}
*{{citation | postscript=.
 | title=On the Absolute Magnitude and Effective Temperature of the Hydrogen-Poor Star HD 30353
 | display-authors=1 | last1=Danziger | first1=I. J.
 | last2=Wallerstein | first2=George | last3=Böhm-Vitense | first3=Erika
 | journal=Astrophysical Journal
 | volume=150 | page=239 | date=October 1967
 | doi=10.1086/149325 | bibcode=1967ApJ...150..239D }}
*{{citation | postscript=.
 | title=Line blanketing effect on the peculiar star HD 30353
 | last=Nariai | first=K.
 | journal=Publications of the Astronomical Society of Japan
 | volume=15 | page=7 | date=1963
 | bibcode=1963PASJ...15....7N }}
*{{citation | postscript=.
 | title=Analysis of the Hydrogen Deficient Star HD 30353
 | last=Nariai | first=K.
 | journal=Publications of the Astronomical Society of Japan
 | volume=15 | page=449 | date=1963
 | bibcode=1963PASJ...15..449N }}
{{Div col end}}

{{Perseus (constellation)}}

{{DEFAULTSORT:KS Persei}}
<!-- Properties -->
[[Category:A-type supergiants]]
[[Category:Chemically peculiar stars]]
[[Category:Spectroscopic binaries]]
<!-- Location/Catalogues -->
[[Category:Perseus (constellation)]]
[[Category:Henry Draper Catalogue objects|030353]]
[[Category:Durchmusterung objects]]
[[Category:Hipparcos objects|022365]]
[[Category:Objects with variable star designations|Persei, KS]]