25 Canum Venaticorum
{{Short description|Star in the constellation Canes Venatici}}
{{Starbox begin
| name = 25 Canum Venaticorum
}}
{{Starbox observe
| epoch = J2000
| constell = Canes Venatici
| dec = {{DEC|+36|17|41.6337}}
| appmag_v = +4.82 {{nowrap|(4.98 + 6.95)}}
}}
{{Starbox character
| type =
| class = {{nowrap|A7 III + A8 V:}}
| b-v =
| u-b =
| variable =
}}
{{Starbox astrometry
| radial_v = {{Val|−10.4|2.1}}
| parallax = 16.42
| p_error = 0.53
}}
{{Starbox orbit
| period = 228
| axis = 1.02
| eccentricity = 0.80
| inclination = 147
| node = 87
| periastron = 1864.0
| periarg = 159
}}
{{Starbox detail
| source =
| component1 = 25 CVn A
| radius =
| luminosity =
| temperature = {{Val|7609|259|fmt=commas}}
| metal_fe =
| component2 = 25 CVn B
}}
{{Starbox catalog
| names = {{odlist | F=25 CVn | BD=+37°2433 | FK5=3083 | HD=118623 | HIP=66458 | HR=5127 | SAO=63648 | GC=18421 | ADS=8974 | CCDM=13375+3617 | WDS=J13375+3618 }}
}}
{{Starbox reference
| Simbad = 25+CVn
}}
{{Starbox end}}
25 Canum Venaticorum is a binary star system in the northern constellation of Canes Venatici, approximately 199 light years from the Sun. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of +4.82 The system is moving closer to the Earth with a heliocentric radial velocity of roughly −10 km/s.
This is a wide binary system with an orbital period of 228 years and an eccentricity of 0.80. As of 2001, they had a projected separation of {{Val|107.0|ul=AU}}. The magnitude 4.98 primary, component A, has a stellar classification of {{nowrap|A7 III}}, which matches an A-type giant star. It is 659 million years old with a projected rotational velocity of 235 km/s. This rate of spin is giving the star an oblate shape with an equatorial bulge that is an estimated 27% larger than the polar radius. The companion, component B, is a magnitude 6.95 A-type main-sequence star with a class of A8 V:. The ':' suffix indicates some uncertainty in the classification of this star.
References
{{reflist|refs=
{{cite simbad | title=25 CVn | access-date=2018-07-27 }}
| 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 }}
| last1=van Belle | first1=Gerard T.
| title=Interferometric observations of rapidly rotating stars
| journal=The Astronomy and Astrophysics Review
| volume=20 | issue=1 | page=51 | date=March 2012
| doi=10.1007/s00159-012-0051-2 | postscript=.
| bibcode=2012A&ARv..20...51V | arxiv=1204.2572 | s2cid=119273474
}}
| title=Validation of the new Hipparcos reduction
| last1=van Leeuwen | first1=F.
| journal=Astronomy and Astrophysics
| volume=474 | issue=2 | pages=653–664 | date=2007
| arxiv=0708.1752 | bibcode=2007A&A...474..653V
| doi=10.1051/0004-6361:20078357 | s2cid=18759600 | postscript=. }}
| title=The VAST Survey - III. The multiplicity of A-type stars within 75 pc
| last1=De Rosa | first1=R. J. | last2=Patience | first2=J.
| last3=Wilson | first3=P. A. | last4=Schneider | first4=A.
| last5=Wiktorowicz | first5=S. J. | last6=Vigan | first6=A.
| last7=Marois | first7=C. | last8=Song | first8=I.
| last9=Macintosh | first9=B. | last10=Graham | first10=J. R.
| last11=Doyon | first11=R. | last12=Bessell | first12=M. S.
| last13=Thomas | first13=S. | last14=Lai | first14=O.
| journal=Monthly Notices of the Royal Astronomical Society
| volume=437 | issue=2 | pages=1216–1240 | year=2014
| bibcode=2014MNRAS.437.1216D | postscript=. | doi=10.1093/mnras/stt1932 | arxiv=1311.7141 | doi-access=free }}
| last1=David | first1=Trevor J. | last2=Hillenbrand | first2=Lynne A.
| title=The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets
| journal=The Astrophysical Journal
| volume=804 | issue=2 | pages=146 | year=2015
| bibcode=2015ApJ...804..146D | arxiv=1501.03154
| doi=10.1088/0004-637X/804/2/146 | s2cid=33401607 | postscript=. }}
| title=A catalogue of multiplicity among bright stellar systems
| last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
| journal=Monthly Notices of the Royal Astronomical Society
| volume=389 | issue=2 | pages=869 | date=2008
| doi=10.1111/j.1365-2966.2008.13596.x
| doi-access=free | bibcode=2008MNRAS.389..869E | postscript=.
| arxiv=0806.2878 | s2cid=14878976 }}
| title=Visual binary orbits and masses POST HIPPARCOS
| last1=Söderhjelm | first1=Staffan
| journal=Astronomy and Astrophysics
| volume=341 | pages=121–140 | date=1999
| bibcode=1999A&A...341..121S | postscript=. }}
| title=The masses of stars above the main sequence
| last1=Stephenson | first1=C. B. | last2=Sanwal | first2=N. B.
| journal=Astronomical Journal | postscript=.
| volume=74 | pages=689–704 | date=June 1969
| doi=10.1086/110845 | bibcode=1969AJ.....74..689S | doi-access=free }}
| display-authors=1 | last1=Mason | first1=B. D.
| last2=Wycoff | first2=G. L. I. | last3=Hartkopf | first3=W. I.
| last4=Douglass | first4=G. G. | last5=Worley | first5=C. E.
| title=The Washington Visual Double Star Catalog (WDS), Version 2019-01-21
| journal=The Astronomical Journal | postscript=.
| volume=122 | issue=6 | pages=3466–3471 | date=December 2001
| doi=10.1086/323920 | bibcode=2001AJ....122.3466M
| publisher=U. S. Naval Observatory, Washington D.C. | doi-access=free }}
}}
{{Stars of Canes Venatici}}
{{DEFAULTSORT:25 Canum Venaticorum}}
Category:A-type main-sequence stars