View source for Astronomy:Beta Reticuli

{{Short description|Star in the constellation Reticulum}}
{{Starbox begin
 | name = Beta Reticuli
}}
{{Starbox image
| image = 
  <div style="position: relative">[[File:Reticulum IAU.svg|250px|alt=Diagram showing star positions and boundaries of the Reticulum constellation and its surroundings]]
  <div style="position: absolute; left: 51.70%; top: 55.0%;">[[File:Cercle rouge 100%.svg|12px]]</div>
  </div>
| caption=Location of β Reticuli (circled)
}}
{{Starbox observe
 | epoch = [[Astronomy:J2000.0|J2000.0]]
 | equinox = [[Astronomy:J2000.0|J2000.0]] ([[Astronomy:International Celestial Reference System|ICRS]])
 | constell = Reticulum
 | ra = {{RA|03|44|11.97587}}<ref name=vanLeeuwen2007/>
 | dec = {{DEC|−64|48|24.8610}}<ref name=vanLeeuwen2007/>
 | appmag_v = +3.84<ref name=Mermilliod1986/>
}}
{{Starbox character
 | class = {{nowrap|K0IV SB}}<ref name=Ramm2009/>
 | b-v = +1.13<ref name=Mermilliod1986/>
 | u-b = +1.11<ref name=Mermilliod1986/>
 | r-i = 
 | variable = 
}}
{{Starbox astrometry
 | radial_v = {{Val|51.1|4.1}}<ref name=deBruijne2012/>
 | prop_mo_ra = +307.13<ref name=vanLeeuwen2007/>
 | prop_mo_dec = +77.50<ref name=vanLeeuwen2007/>
 | parallax = 33.49
 | p_error = 0.53
 | parallax_footnote = <ref name=vanLeeuwen2007/>
 | absmag_v = {{Val|+1.46|0.03}}<ref name=Ramm2009/>
}}
{{Starbox orbit
 | reference = <ref name=Ramm2009/>
 | period_unitless = {{Val|1918.31|0.73|fmt=commas|u=d}}
 | axis_unitless = {{Val|27.8|0.46|u=mas}}
 | node = {{Val|16|4.4}}
 | eccentricity = {{Val|0.33461|0.00035}}
 | inclination = {{Val|82.85|3.0}}
 | periastron = {{nowrap|2452806.14 ± 0.33}}
 | periarg = {{Val|42.023|0.084}}
 | k1 = {{Val|5.1235|0.0025}}
}}
{{Starbox detail
 | source = 
 | component1 = β Ret A
 | mass = {{Val|1.2|0.2}}<ref name=Ramm2009/>
 | radius = {{Val|9.3|0.4}}<ref name=Ramm2009/>
 | luminosity = 
 | temperature = {{Val|4580|80|fmt=commas}}<ref name=Ramm2009/>
 | gravity = 
 | metal_fe = 
 | rotational_velocity = 
 | age_gyr = 5–6<ref name=Ramm2009/>
 | component2 = β Ret B
 | mass2 = {{Val|0.4|0.1}}<ref name=Ramm2009/>
}}
{{Starbox catalog
 | names = [[Astronomy:Bayer designation|β&nbsp;Ret]], [[Astronomy:Durchmusterung|CPD]]−65°&nbsp;263, FK5&nbsp;141, HD&nbsp;23817, HIP&nbsp;17440, HR&nbsp;1175, [[Astronomy:Smithsonian Astrophysical Observatory Star Catalog|SAO]]&nbsp;248877, [[Astronomy:Washington Double Star Catalog|WDS]]&nbsp;J03442-6448A.<ref name=SIMBAD/>
}}
{{Starbox reference
|Simbad=bet+Ret
}}
{{Starbox end}}  
'''Beta&nbsp;Reticuli''' ('''Beta&nbsp;Ret''', '''β&nbsp;Reticuli''', '''β&nbsp;Ret''') is [[Astronomy:Binary star|binary star]]<ref name=Eggleton2008/> system in southern constellation of Reticulum. It is visible to the naked eye with an [[Astronomy:Apparent visual magnitude|apparent visual magnitude]] of +3.84.<ref name=Mermilliod1986/> Based upon an annual [[Astronomy:Stellar parallax|parallax shift]] of 33.49&nbsp;mas,<ref name=vanLeeuwen2007/> it is located some 97&nbsp;[[Light year|light year]]s from our [[Astronomy:Sun|Sun]].

This is a single-lined [[Astronomy:Spectroscopic binary|spectroscopic binary]] with an [[Astronomy:Orbital period|orbital period]] of 5.25&nbsp;years and an [[Astronomy:Orbital eccentricity|eccentricity]] of 0.33. The primary, component A, is an [[Astronomy:Stellar evolution|evolved]] [[Astronomy:K-type star|K-type]] [[Astronomy:Giant star|giant star]] with a [[Astronomy:Stellar classification|stellar classification]] of K0&nbsp;IVSB:. It is between 5 and 6 billion years old, with 1.2 times the [[Astronomy:Solar mass|mass of the Sun]] and 9.3 times the [[Astronomy:Solar radius|Sun's radius]]. The companion, component B, is most likely a [[Astronomy:Red dwarf|red dwarf]] with a classification in the range M0–M4.<ref name=Ramm2009/>

During the mid-20th century, the Dutch-American astronomer Willem Jacob Luyten proposed that the G3V star HD&nbsp;24293 formed a third component of this system, based upon similar [[Astronomy:Proper motion|proper motion]]s. However, this was subsequently ruled out based on more accurate measurements, since their actual distances, radial velocities, and proper motions do not match.<ref name=Caballero2009>{{citation
 | title=Reaching the boundary between stellar kinematic groups and very wide binaries. The Washington double stars with the widest angular separations
 | last1=Caballero | first1=J. A.
 | journal=Astronomy and Astrophysics
 | volume=507 | issue=1 | pages=251–259
 | date=November 2009 | postscript=.
 | doi=10.1051/0004-6361/200912596 | bibcode=2009A&A...507..251C |arxiv = 0908.2761 | s2cid=118194112 }}</ref>

Beta Reticuli is moving through the Galaxy at a speed of 69.2&nbsp;km/s relative to the Sun. Its projected Galactic orbit carries it between 10,100 and 24,200 light years from the center of the Galaxy.<ref name=astrostudio>[http://www.astrostudio.org/xhip.php?hip=17440 Beta Reticuli (HIP 17440)] {{webarchive |url=https://web.archive.org/web/20130102052640/http://www.astrostudio.org/xhip.php?hip=17440 |date=January 2, 2013 }}</ref> Beta Reticuli came closest to the Sun 319,000 years ago when it had brightened to magnitude 2.98 from a distance of 67 light years.<ref name=astrostudio/>

==Naming==
In [[Social:Chinese language|Chinese]] caused by adaptation of the European southern hemisphere constellations into the Chinese system, {{lang|zh|蛇首}} ({{lang|zh-Latn|Shé Shǒu}}), meaning ''[[Astronomy:Chinese constellations#The Southern Asterisms|Snake's Head]]'', refers to an asterism consisting of β Reticuli and [[Astronomy:Alpha Hydri|α Hydri]]. Consequently, β Reticuli itself is known as {{lang|zh|蛇首二}} ({{lang|zh-Latn|Shé Shǒu èr}}, {{lang-en|the Second Star of Snake's Head}}.)<ref>{{in lang|zh}} [http://aeea.nmns.edu.tw/2006/0607/ap060727.html AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 27 日]</ref>

==References==
{{reflist|refs=

<ref name=vanLeeuwen2007>{{citation
 | 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=. }}</ref>

<ref name=Mermilliod1986>{{citation
 | last1=Mermilliod | first1=J.-C.
 | title=Compilation of Eggen's UBV data, transformed to UBV (unpublished)
 | journal=Catalogue of Eggen's UBV Data
 | year=1986 | publisher=[[Astronomy:SIMBAD|SIMBAD]]
 | bibcode=1986EgUBV........0M | postscript=. }}</ref>

<ref name=Caballero2009>{{citation
 | title=Reaching the boundary between stellar kinematic groups and very wide binaries. The Washington double stars with the widest angular separations
 | last1=Caballero | first1=J. A.
 | journal=Astronomy and Astrophysics
 | volume=507 | issue=1 | pages=251–259
 | date=November 2009 | postscript=.
 | doi=10.1051/0004-6361/200912596 | bibcode=2009A&A...507..251C |arxiv = 0908.2761 | s2cid=118194112 }}</ref>

<ref name=deBruijne2012>{{citation
 | last1=de Bruijne | first1=J. H. J. | last2=Eilers | first2=A.-C. 
 | title=Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project 
 | journal=Astronomy & Astrophysics
 | volume=546 | id=A61 | pages=14 | date=October 2012
 | doi=10.1051/0004-6361/201219219 | bibcode=2012A&A...546A..61D 
 | arxiv=1208.3048 | s2cid=59451347 | postscript=. }}</ref>

<ref name=Ramm2009>{{citation
 | title=Spectroscopic orbits for K giants β Reticuli and ν Octantis: what is causing a low-amplitude radial velocity resonant perturbation in ν Oct?
 | last1=Ramm | first1=D. J. | last2=Pourbaix | first2=D.
 | last3=Hearnshaw | first3=J. B. | last4=Komonjinda | first4=S.
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=394 | issue=3 | pages=1695–1710 | date=April 2009
 | doi=10.1111/j.1365-2966.2009.14459.x | bibcode=2009MNRAS.394.1695R
 | display-authors=1 | postscript=. | doi-access=free }}</ref>

<ref name=Eggleton2008>{{citation
 | last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
 | title=A catalogue of multiplicity among bright stellar systems
 | journal=[[Organization:Monthly Notices of the Royal Astronomical Society|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 | bibcode=2008MNRAS.389..869E
 | arxiv=0806.2878 | s2cid=14878976 | postscript=. }}</ref>

<ref name=SIMBAD>{{cite simbad
 | title=* bet Ret
 | access-date=2017-02-13 }}</ref>

}}

{{Stars of Reticulum|state=collapsed}}

{{DEFAULTSORT:Beta Reticuli}}
[[Category:K-type giants]]
[[Category:M-type main-sequence stars]]
[[Category:Spectroscopic binaries]]
[[Category:Bayer objects|Reticuli, Beta]]
[[Category:Henry Draper Catalogue objects|023817]]
[[Category:Hipparcos objects|017440]]
[[Category:Bright Star Catalogue objects|1175]]
[[Category:Durchmusterung objects]]

{{Sourceattribution|Beta Reticuli}}