Editing Gacrux (section)

{{Short description|Star in the constellation Crux}}
{{Starbox begin
 | name = γ Crucis
}}
{{Starbox image
 | image = [[File:Gacrux.jpg|250px]]
 | caption = Gacrux, γ Crucis
}}
{{Starbox observe
 | pronouce = {{IPAc-en|'|g|æ|k|r|V|k|s}},<ref>{{cite web |url=https://www.starrynighteducation.com/resources_pronunciation.html |title=Audio Pronunciation Guide |date=2009 |website=Starry Night Education |publisher=Simulation Curriculum Corp. |access-date=26 Apr 2019 }}</ref>
 | epoch    = [[J2000.0]]
 | equinox  = [[J2000.0]]
 | constell = [[Crux]]
 | ra       = {{RA|12|31|09.960}}<ref name=aaa474_2_653/>
 | dec      = {{DEC|−57|06|47.57}}<ref name=aaa474_2_653/>
 | appmag_v = +1.64<ref name=ducati>{{cite journal|bibcode=2002yCat.2237....0D|title=VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system|journal=CDS/ADC Collection of Electronic Catalogues|volume=2237|pages=0|last1=Ducati|first1=J. R.|date=2002}}</ref>
}}
{{Starbox character
| type      = [[Red giant branch]]
| class     = M3.5&nbsp;III<ref name=mnras400_4_1945/> 
| appmag_1_passband = J
| appmag_1  = −1.99
| b-v       = +1.59<ref name=ducati/>
| u-b       = +1.78<ref name=ducati/>
| variable  = [[Semiregular variable star|SRV]]<ref name=mnras400_4_1945/>
}}
{{Starbox astrometry
| radial_v  = +20.6<ref name=scfs/>
| prop_mo_ra  = +28.23
| prop_mo_dec = −265.08
| pm_footnote = <ref name=aaa474_2_653/>
| parallax  = 36.83
| p_error   = 0.18
| parallax_footnote = <ref name=aaa474_2_653/>
| absmag_v = {{val|-0.68|0.01}}<ref name=neuhauser>{{Cite journal |last1=R. |first1=Neuhäuser |last2=G. |first2=Torres |last3=M. |first3=Mugrauer |last4=L. |first4=Neuhäuser, D. |last5=J. |first5=Chapman |last6=D. |first6=Luge |last7=Matteo |first7=Cosci |date=2022 |title=Colour evolution of Betelgeuse and Antares over two millennia, derived from historical records, as a new constraint on mass and age |url=https://hdl.handle.net/10278/5003332 |journal=Monthly Notices of the Royal Astronomical Society |language=it |volume=516 |issue=1 |doi=10.1093/mnra |doi-broken-date=1 November 2024 |hdl=10278/5003332 |issn=0035-8711}}</ref>
}}
{{Starbox detail
 | mass = 1.5{{±|0.2}}<ref name="kallinger"/>
 | radius = 73<ref name="Nielsen2023"/>
 | gravity = {{val|0.75|0.02}}<ref name="kallinger"/>
 | luminosity = 830<ref name="kallinger"/>
 | temperature = {{val|3689|125}}<ref name="kallinger"/>
 | metal_fe =
 | rotational_velocity =
 | age_myr =
}}
{{Starbox catalog
 | names = {{odlist | name=Gacrux | CD=−56&nbsp;4504 | B=γ Crucis | Gl=470 | HD=108903 | HIP=61084 | HR=4763 | LTT=4752 | SAO=240019 }}
}}
{{Starbox reference
 | Simbad = HD+108903
}}
{{Starbox end}}

'''Gacrux''' is the third-brightest star in the southern constellation of [[Crux]], the Southern Cross. It has the [[Bayer designation]] '''Gamma Crucis''', which is [[Latinisation of names|Latinised]] from '''γ Crucis''' and abbreviated '''Gamma Cru''' or '''γ Cru'''. With an [[apparent visual magnitude]] of +1.63,<ref name=clpl4/> it is the [[list of brightest stars|26th brightest star]] in the [[night sky]]. A line from the two "Pointers", [[Alpha Centauri]] through [[Beta Centauri]], leads to within 1° north of this star. Using [[parallax]] measurements made during the [[Hipparcos]] mission, it is {{Convert|88.6|ly|pc|abbr=off|lk=on}} distant.<ref name=aaa474_2_653/> It is the nearest M-type [[red giant]] star.<ref name=mnras350_1_365/>