Alpha Columbae
{{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 = J2000.0
| constell = Columba
| dec = {{DEC|−34|04|26.7950}}
}}
{{Starbox character
| class = B9Ve or B7 IV
}}
{{Starbox astrometry
| parallax = 12.48
| p_error = 0.36
}}
{{Starbox detail
| temperature={{val|12200|122|fmt=commas}}
}}
{{Starbox catalog
| names = {{odlist | B=Alpha Col, 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 }}
}}
{{Starbox reference
| Simbad=alf+Col
}}
{{Starbox end}}
Alpha Columbae or α Columbae, officially named Phact ({{IPAc-en|'|f|æ|k|t}}),{{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
}}{{cite web | url=http://www.pas.rochester.edu/~emamajek/WGSN/IAU-CSN.txt | title=IAU Catalog of Star Names |accessdate=28 July 2016}} is a third magnitude star in the southern constellation of Columba. It has an apparent visual magnitude of 2.6, 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}}.
Nomenclature
α Columbae, Latinized to Alpha Columbae, is the star's Bayer designation.
The traditional name of Phact (also rendered Phad, Phaet, Phakt) derives from the Arabic فاختة fākhitah 'ring dove'. It was originally applied to the constellation Cygnus and later transferred to this star.{{cite book
|author= Davis, Jr. G. A.
|date = 1971
|title = Pronunciations, Derivations, and Meanings of a Selected List of Star Names
|edition = Reprint
|publisher = Sky Pub. Corp
|page = 11}}{{cite book
|author= Kunitzsch, P.
|date = 1959
|title = Arabische Sternnamen in Europa
|publisher = Otto Harrassowitz
|location = Wiesbaden
|pages = 191–192}}{{cite book
|author= Laffitte, R.
|date = 2005
|title = Héritages arabes: Des noms arabes pour les étoiles
|edition = 2éme revue et corrigée
|publisher = Librairie Orientaliste Paul Geunthner / Les Cahiers de l'Orient
|location = Paris
|page = 223}}{{cite book
|author= Kunitzsch, P.
|author2= Smart, T.
|name-list-style= amp
|date = 2006
|title = A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations
|edition = 2nd rev.
|publisher = Sky Pub
|location = Cambridge, MA
|isbn = 978-1-931559-44-7
|page = 30}} The etymology of its name hadāri (unknown meaning){{cite book
|author = Allen, R. H.
|author-link = Richard Hinckley Allen
|date = 1963
|title = Star Names: Their Lore and Meaning
|edition = Reprint
|publisher = Dover Publications Inc.
|isbn = ((0-486-21079-0))
|page = [https://archive.org/details/starnamestheirlo00alle/page/167 167]
}} has also been suggested. In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN){{cite web | url=https://www.iau.org/science/scientific_bodies/working_groups/280/ | title=IAU Working Group on Star Names (WGSN)|accessdate=22 May 2016}} to catalog and standardize proper names for stars. The WGSN's first bulletin of July 2016{{cite web | url=http://www.pas.rochester.edu/~emamajek/WGSN/WGSN_bulletin1.pdf | title=Bulletin of the IAU Working Group on Star Names, No. 1 |accessdate=28 July 2016}} 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.{{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}}. 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}}.).{{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. From this Chinese name, the name Chang Jin has appeared[https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Columba_Noae*.html Richard Hinckley Allen: Star Names — Their Lore and Meaning: Columbae]
Properties
This is believed to be a solitary star, although it has a faint optical companion at an angular separation of 13.5 arcseconds, making it a double star. The stellar classification of Alpha Columbae is B9Ve, 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. Like most if not all such stars, it is rotating rapidly with a projected rotational velocity of {{nowrap|176 km s−1}}. The azimuthal equatorial velocity may be {{nowrap|457 km s−1}}. It is a suspected Gamma Cassiopeiae type (GCAS) variable star, with its apparent magnitude varying from 2.62m to 2.66m.
References
{{Reflist|refs=
| 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=. }}
{{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 }}
{{cite simbad|title=alf Col|accessdate=April 21, 2009}}
[http://vizier.u-strasbg.fr/viz-bin/VizieR-S?HR%201956 HR 1956], database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID [http://vizier.u-strasbg.fr/viz-bin/Cat?V/50 V/50]. Accessed on line April 21, 2009.
[http://vizier.u-strasbg.fr/viz-bin/VizieR?-6N&-out.form=H0&//*&-source%3DV/50/notes&HR%3D1956 Note of HR 1956], database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID [http://vizier.u-strasbg.fr/viz-bin/Cat?V/50 V/50]. Accessed on line April 21, 2009.
| 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 | postscript=. }}
}}
{{Stars of Columba}}
{{DEFAULTSORT:Alpha Columbae}}
Category:B-type main-sequence stars
Category:Columba (constellation)