{{Short description|Star in the constellation Columba}} {{Starbox begin}} {{Starbox image | image = {{Location mark | image=Columba IAU.svg | float=center | width=240 | position=right | mark=Red circle.svg | mark_width=10 | mark_link=α Col | x%=58.0 | y%=36.2 }} | caption = Location of α Columbae (circled) }} {{Starbox observe | epoch = J2000 | constell = Columba<ref name=Anderson2012/> | ra = {{RA|05|39|38.94103}}<ref name=aaa474_2_653/> | dec = {{DEC|−34|04|26.7950}}<ref name=aaa474_2_653/> | appmag_v = 2.645<ref name=mnassa31_69/> }} {{Starbox character | class = B9Ve<ref name=levenhagen_Leister_2006/> or B7 IV<ref name=houk1979/> | u-b = −0.44<ref name=mnassa31_69/> | b-v = −0.125<ref name=mnassa31_69/> | r-i = −0.09<ref name=bsc1 /> | variable = γ Cas?<ref name=Samus_et_al_2017/> }} {{Starbox astrometry | radial_v = +35.0<ref name=gcsrv/> | prop_mo_ra = −1.58<ref name=aaa474_2_653/> | prop_mo_dec = −24.82 | pm_footnote = <ref name=aaa474_2_653/> | parallax = 12.48 | p_error = 0.36 | parallax_footnote = <ref name=aaa474_2_653/> | absmag_v = −1.87<ref name=Anderson2012/> }} {{Starbox detail | radius = {{val|7|0.14}}<ref name=arcos/> | mass = 4.5<ref name=kaler /> | temperature = {{val|12200|122|fmt=commas}}<ref name=arcos/> | gravity = {{val|3.5|0.04}}<ref name=arcos/> | luminosity = 3,311<ref name=Balona_Ozuyar_2021/> | rotational_velocity = 176<ref name=aaa489_2_627/> | age_myr = 93<ref name=levenhagen_Leister_2006/> }} {{Starbox catalog | names = {{odlist | name=Phact | B=α Col | CCDM= J05396−3404 A | CD=−34 2375 | CPD=−34 703 | FK5=215 | GC=7078 | HD=37795 | HIP=26634 | HR=1956 | NSV=2549 | PPM=281732 | SAO=196059 }}<ref name=sb0 /> }} {{Starbox reference | Simbad=alf+Col }} {{Starbox end}}
'''Alpha Columbae''' is a third magnitude star in the southern constellation of Columba. It has the proper name '''Phact''' ({{IPAc-en|'|f|æ|k|t}});<ref name=Kunitzsch_2006/><ref name="IAU-CSN"/> ''Alpha Columbae'' is the Bayer designation, which is Latinized from '''α Columbae'''. This star has an apparent visual magnitude of 2.6,<ref name=mnassa31_69/> making it the brightest member of Columba. Based upon parallax measurements made during the Hipparcos mission, Alpha Columbae is located at a distance of around {{Convert|261|ly|pc|abbr=off|lk=on}}.<ref name=aaa474_2_653/>
== Nomenclature == ''α Columbae'', Latinized to ''Alpha Columbae'', is the star's Bayer designation. It is abbreviated Alpha Col or α Col.
The traditional name of ''Phact'' (also rendered ''Phad'', ''Phaet'', ''Phakt'')<ref name=bsc2 /> derives from the Arabic فاختة ''fākhitah'' 'ring dove'. It was originally applied to the constellation Cygnus and later transferred to this star.<ref name=Davis_1971/><ref name=Kunitzsch_1959/><ref name=Laffitte_2005/><ref name=Kunitzsch_Smart_2006/> The etymology of its name ''<u>h</u>a<u>d</u>āri'' (unknown meaning)<ref name=Allen_1963/> has also been suggested. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN)<ref name="WGSN"/> to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016<ref name="WGSN1"/> included a table of the first two batches of names approved by the WGSN; which included ''Phact'' for this star.
In Chinese, {{lang|zh|丈人}} ({{lang|zh-Latn|Zhàng Rén}}), meaning ''Grandfather'', refers to an asterism consisting of α Columbae and ε Columbae.<ref>{{in lang|zh}} ''中國星座神話'', written by 陳久金. Published by 台灣書房出版有限公司, 2005, {{ISBN|978-986-7332-25-7}}.</ref> Consequently, α Columbae itself is known as {{lang|zh|丈人一}} ({{lang|zh-Latn|Zhàng Rén yī}}, {{langx|en|the First Star of Grandfather}}).<ref>{{in lang|zh}} [http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_n_r.htm 香港太空館 - 研究資源 - 亮星中英對照表] {{webarchive|url=https://web.archive.org/web/20110130063024/http://www.lcsd.gov.hk/CE/Museum/Space/Research/StarName/c_research_chinengstars_n_r.htm |date=2011-01-30 }}, Hong Kong Space Museum. Accessed on line November 23, 2010.</ref> From this Chinese name, the name ''Chang Jin'' has appeared.<ref name=Penelope/>
== Properties == This is believed to be a solitary star,<ref name=aaa489_2_627/><ref name=mnras389_2_869/> although it has a faint optical companion at an angular separation of 13.5 arcseconds, making it a double star.<ref name=dommanget_nys2002/> The stellar classification of Alpha Columbae is B9Ve,<ref name=levenhagen_Leister_2006/> matching a B-type main-sequence star. The spectrum shows it to be a Be star surrounded by a hot gaseous disk, which is generating emission lines because of hydrogen recombination.<ref name=bsc2/> Like most if not all such stars, it is rotating rapidly with a projected rotational velocity of {{nowrap|176 km s<sup>−1</sup>}}. The azimuthal equatorial velocity may be {{nowrap|457 km s<sup>−1</sup>}}.<ref name=aaa489_2_627/> It is a suspected Gamma Cassiopeiae type (GCAS) variable star, with its apparent magnitude varying from 2.62<sup>m</sup> to 2.66<sup>m</sup>.<ref name=Samus_et_al_2017/>
==References== {{Reflist|refs=
<ref name="IAU-CSN">{{cite web | title=IAU Catalog of Star Names | first=Eric | last=Mamajek | publisher=University of Rochester | url=http://www.pas.rochester.edu/~emamajek/WGSN/IAU-CSN.txt | accessdate=28 July 2016 }}</ref>
<ref name="WGSN1">{{cite web | title=Bulletin of the IAU Working Group on Star Names, No. 1 | first=Eric | last=Mamajek | publisher=University of Rochester | url=http://www.pas.rochester.edu/~emamajek/WGSN/WGSN_bulletin1.pdf |accessdate=28 July 2016}}</ref>
<ref name="WGSN">{{cite web | title=IAU Working Group on Star Names (WGSN) | publisher=International Astronomical Union | url=https://www.iau.org/science/scientific_bodies/working_groups/280/ | accessdate=22 May 2016 | archive-date=10 June 2016 | archive-url=https://web.archive.org/web/20160610172014/https://www.iau.org/science/scientific_bodies/working_groups/280/ | url-status=dead }}</ref>
<ref name=Davis_1971>{{cite book | last=Davis, Jr. | first=G. A. | title = Pronunciations, Derivations, and Meanings of a Selected List of Star Names | edition = Reprint | page=11 | year=1971 | publisher=Sky Publishing Corp | location=Cambridge, MA }}</ref>
<ref name=Kunitzsch_2006>{{cite book | last1=Kunitzsch |first1=Paul | last2=Smart | first2=Tim | date = 2006 | edition = 2nd rev. | title = A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations | publisher = Sky Pub |location = Cambridge, Massachusetts | isbn = 978-1-931559-44-7 }}</ref>
<ref name=Kunitzsch_1959>{{cite book | last= Kunitzsch | first=P. | date = 1959 | title = Arabische Sternnamen in Europa | publisher = Otto Harrassowitz | location = Wiesbaden | pages = 191–192}}</ref>
<ref name=Laffitte_2005>{{cite book | last=Laffitte | first=R. | date = 2005 | title = Héritages arabes: Des noms arabes pour les étoiles | edition = 2<sup>éme</sup> revue et corrigée | publisher = Librairie Orientaliste Paul Geunthner / Les Cahiers de l'Orient | location = Paris | page = 223 }}</ref>
<ref name=Kunitzsch_Smart_2006>{{cite book | last1=Kunitzsch | first1=P. | last2=Smart | first2=T. | title=A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations | edition=2nd rev. | date=2006 | page=30 | publisher=Sky Pub | location=Cambridge, MA | isbn=978-1-931559-44-7 }}</ref>
<ref name=Allen_1963>{{cite book | last=Allen | first=R. H. | author-link=Richard Hinckley Allen | title=Star Names: Their Lore and Meaning | edition=Reprint | date=1963 | page=167 | publisher=Dover Publications Inc. | location=New York, NY | url=https://archive.org/details/starnamestheirlo00alle/page/167 | access-date=2026-05-17 }} {{ISBN|0-486-21079-0}}.</ref>
<ref name=Penelope>{{cite web | first=Richard Hinckley | last=Allen | title=Columbae | work=Star Names — Their Lore and Meaning | url=https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Columba_Noae*.html | access-date=2026-05-17 }}</ref>
<ref name=aaa474_2_653>{{cite journal | first=F. | last=van Leeuwen |date=November 2007 | title=Validation of the new Hipparcos reduction | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | bibcode=2007A&A...474..653V | s2cid=18759600 | doi=10.1051/0004-6361:20078357 |arxiv = 0708.1752 }}</ref>
<ref name=arcos>{{Cite journal | last1=Arcos | first1=C. | last2=Kanaan | first2=S. | last3=Chávez | first3=J. | last4=Vanzi | first4=L. | last5=Araya | first5=I. | last6=Curé | first6=M. | display-authors=1 | title=Stellar parameters and H α line profile variability of Be stars in the BeSOS survey | journal=Monthly Notices of the Royal Astronomical Society | volume=474 | issue=4 | pages=5287–5299 | date=January 3, 2018 | doi=10.1093/mnras/stx3075 | doi-access=free | issn=0035-8711|arxiv=1711.08675 | bibcode=2018MNRAS.474.5287A }}</ref>
<ref name=Anderson2012>{{cite XHIP | 26634 | mode=cs2 }}</ref>
<ref name=mnassa31_69>{{Cite journal | title=UBV Photometry of Some Very Bright Stars | last=Cousins | first=A. W. J. | journal=Monthly Notes of the Astronomical Society of Southern Africa | volume=31 | page=69 | date=1972 | bibcode=1972MNSSA..31...69C }}</ref>
<ref name=houk1979>{{cite book | title=Michigan catalogue of two-dimensional spectral types for the HD stars | last1=Houk | first1=Nancy | volume=3 | date=1979 | location=Ann Arbor, Michigan | publisher=Dept. of Astronomy, University of Michigan | bibcode=1982mcts.book.....H }}</ref>
<ref name=gcsrv>{{cite journal | last=Wilson | first=R. E. | date=1953 | title=General Catalogue of Stellar Radial Velocities | journal=Carnegie Institute Washington D.C. Publication | publisher=Carnegie Institute of Washington D.C. | bibcode=1953GCRV..C......0W }}</ref>
<ref name=mnras389_2_869>{{cite journal | 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 | arxiv=0806.2878 | s2cid=14878976 }}</ref>
<ref name=aaa489_2_627>{{cite journal | display-authors=1 | last1=Oudmaijer | first1=R. D. | last2=Parr | first2=A. M. | last3=Baines | first3=D. | last4=Porter | first4=J. M. | title=Sub-milliarcsecond precision spectro-astrometry of Be stars | journal=Astronomy and Astrophysics | volume=489 | issue=2 | pages=627–631 |date=October 2008 | doi=10.1051/0004-6361:20079117 | arxiv=0807.3673 | bibcode=2008A&A...489..627O | s2cid=10317142 }}</ref>
<ref name=kaler>{{cite web | first=James B. | last=Kaler | author-link=James B. Kaler | title=Phact | work=STARS | url=http://stars.astro.illinois.edu/sow/phact.html | access-date=2026-05-17 }}</ref>
<ref name=sb0>{{cite simbad | title=alf Col | accessdate=April 21, 2009}}</ref>
<ref name=bsc1>{{cite book | chapter=HR 1956 database entry | title=The Bright Star Catalogue | edition=5th Revised Ed. (Preliminary Version) | first1=D. | last1=Hoffleit | first2=W. H. | last2=Warren, Jr. | chapter-url=http://vizier.u-strasbg.fr/viz-bin/VizieR-S?HR%201956 | access-date=2009-04-21 }} CDS ID [http://vizier.u-strasbg.fr/viz-bin/Cat?V/50 V/50]</ref>
<ref name=dommanget_nys2002>{{cite book | chapter=CCDM J05396-3404 database entry | first1=J. | last1=Dommanget | first2=O. | last2=Nys | year=2002 | title=Catalogue of the Components of Double and Multiple Stars | chapter-url=http://vizier.u-strasbg.fr/viz-bin/VizieR-S?CCDM%20J05396-3404 | access-date=2009-04-21 }}</ref>
<ref name=bsc2>{{cite book | chapter=Note of HR 1956 database entry | title=The Bright Star Catalogue | edition=5th Revised Ed. (Preliminary Version) | first1=D. | last1=Hoffleit | first2=W. H. | last2=Warren, Jr. | chapter-url=http://vizier.u-strasbg.fr/viz-bin/VizieR?-6N&-out.form=H0&//*&-source%3DV/50/notes&HR%3D1956 | access-date=2009-04-21 }} CDS ID [http://vizier.u-strasbg.fr/viz-bin/Cat?V/50 V/50]</ref>
<ref name=levenhagen_Leister_2006>{{cite journal | last1=Levenhagen | first1=R. S. | last2=Leister | first2=N. V. | title=Spectroscopic analysis of southern B and Be stars | journal=Monthly Notices of the Royal Astronomical Society | volume=371 | pages=252–262 | year=2006 | issue=1 | bibcode=2006MNRAS.371..252L | doi=10.1111/j.1365-2966.2006.10655.x | doi-access=free | arxiv=astro-ph/0606149 | s2cid=16492030 }}</ref>
<ref name=Samus_et_al_2017>{{cite journal | title=General Catalogue of Variable Stars | display-authors=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. | version=GCVS 5.1 | journal=Astronomy Reports | year=2017 | volume=61 | issue=1 | pages=80–88 | doi=10.1134/S1063772917010085 | bibcode=2017ARep...61...80S | s2cid=255195566 }}</ref>
<ref name=Balona_Ozuyar_2021>{{cite journal | title=TESS Observations of be Stars: General Characteristics and the Impulsive Magnetic Rotator Model | last1=Balona | first1=Luis A. | last2=Ozuyar | first2=Dogus | journal=The Astrophysical Journal | date=2021 | volume=921 | issue=1 | page=5 | doi=10.3847/1538-4357/ac1a77 | doi-access=free | arxiv=2008.06288 | bibcode=2021ApJ...921....5B }}</ref> }} {{Stars of Columba}}
<!-- Properties --> Category:B-type main-sequence stars Category:Be stars <!-- Constellation & catalogues --> Category:Columba (constellation) Columbae, Alpha 1956 CD-34 02375 037795 026634 Phact Category:Lucidae