{{Short description|Star in the constellation Boötes}}{{distinguish|Rho Boötis}} {{Starbox begin}} {{Starbox image | image = [[Image:RBooLightCurve.png|250px]] | caption = The [[Photometric_system#Photometric_letters|visual band]] [[light curve]] of R Boötis, from AAVSO data<ref name="aavso"/> }} {{Starbox observe | epoch = J2000 | ra = {{RA|14|37|11.57616}}<ref name=GaiaEDR3/> | dec = {{DEC|26|44|11.6562}}<ref name=GaiaEDR3/> | appmag_v = 6.0 - 13.3<ref name=Samus_et_al_2017/> | constell = [[Boötes]] }} {{Starbox character | type = [[asymptotic giant branch|AGB]]<ref name=wu2022/> | class = M4-8e<ref name=Keenan_et_al_1974/> | b-v = {{val|1.50|0.51}}<ref name=Anderson_Francis_2012/> | u-b = | variable = [[Mira variable]]<ref name=Samus_et_al_2017/><ref name="AAVSO"/> }} {{Starbox astrometry | radial_v = {{val|−58.0|4.7}}<ref name=Gontcharov2006/> | prop_mo_ra = –25.537<ref name=GaiaEDR3/> | prop_mo_dec = 11.968<ref name=GaiaEDR3/> | parallax = 1.5204 | p_error = 0.0586 | parallax_footnote = <ref name=GaiaEDR3/> | absmag_v = }} {{Starbox detail | mass = 1.492<ref name=Anders2021/> | radius = 241{{snd}}268<ref name=Béguin2024/> | luminosity = {{val|4255|1009|821|fmt=commas}}<ref name=Béguin2024/> | temperature = 3,029{{snd}}3,061<ref name=Béguin2024/> | metal_fe = +0.512<ref name=Anders2021/> | gravity = {{val|-0.33}} or {{val|-0.25}}<ref name=Béguin2024/> | rotational_velocity = | age_gyr = }} {{Starbox catalog | names = {{odlist | V=R Boo | BD=+27°2400 | GC=19706 | HD=128609 | HIP=71490 | SAO=83440 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad=R+Boo }} {{Starbox end}}
'''R Boötis''' is a [[variable star]] in the northern [[constellation]] of [[Boötes]]. The star's brightness varies tremendously, ranging from [[apparent magnitude]] 6.0, when it might be faintly visible to the [[naked eye]] under very good observing conditions, to 13.3, when a fairly large telescope would be required to see it.<ref name=Samus_et_al_2017/> The distance to this star is approximately {{val|2,150|fmt=commas|ul=light years}} based on [[stellar parallax|parallax]] measurements.<ref name=GaiaEDR3/> It is drifting closer with a [[radial velocity]] of about −58 km/s.<ref name=Gontcharov2006/>
The variability of this star was discovered by German astronomer [[Friedrich Wilhelm Argelander|F. W. Argelander]] in 1857.<ref name=Isles_Saw_1987/> It is classified as a [[Mira variable|Mira-type]] [[Pulsating star|pulsating variable]] that ranges in brightness from magnitude 6.0 down to 13.3 with a period of 223.11 days.<ref name=Samus_et_al_2017/><ref name="AAVSO"/> The [[stellar classification]] of the star ranges from M4e to M8e,<ref name=Keenan_et_al_1974/> where the 'e' indicates [[Emission lines|emission features]] in the spectrum.
R Boötis is much larger and luminous than the Sun, at {{val|4000|fmt=commas|u=[[solar luminosity|solar luminosities]]}} and a size 250 times that of the Sun. It has cooled to an [[effective temperature]] of {{val|3000|fmt=commas|u=[[Kelvin]]s}},<ref name=Béguin2024/> giving it a reddish hue.<ref name=csiro/>
==References== {{Reflist|refs=
<ref name="aavso">{{cite web |title=Download Data |url=https://www.aavso.org/data-download |website=aavso.org |publisher=AAVSO |access-date=1 October 2021}}</ref>
<ref name=SIMBAD>{{cite simbad | title=R Boo | access-date=2021-05-01 }}</ref>
<ref name=GaiaEDR3>{{Cite Gaia EDR3|1279554668255201152}}</ref>
<ref name=csiro>{{citation | title=The Colour of Stars | date=December 21, 2004 | work=Australia Telescope, Outreach and Education | publisher=Commonwealth Scientific and Industrial Research Organisation | url=http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html | accessdate=2012-01-16 | archive-date=2013-12-03 | archive-url=https://web.archive.org/web/20131203222826/http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html | url-status=dead }}</ref>
<ref name=wu2022>{{cite journal |bibcode=2022MNRAS.516.1881W |title=Water-maser survey towards off-plane O-rich AGBs around the orbital plane of the Sagittarius stellar stream |last1=Wu |first1=Yuanwei |last2=Zhang |first2=Bo |last3=Li |first3=Jingjing |last4=Zheng |first4=Xing-Wu |journal=Monthly Notices of the Royal Astronomical Society |date=2022 |volume=516 |issue=2 |page=1881 |doi=10.1093/mnras/stac1971 |doi-access=free |arxiv=2207.05914 }}</ref>
<ref name=Samus_et_al_2017>{{cite journal | 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. | title=General Catalogue of Variable Stars | version=5.1 | journal=[[Astronomy Reports]] | year=2017 | volume=61 | issue=1 | pages=80–88 | bibcode=2017ARep...61...80S | s2cid=125853869 | doi=10.1134/S1063772917010085 }}</ref>
<ref name=Isles_Saw_1987>{{cite journal | title=106 Mira Stars, - I. R Ari, R Aur, X Aur, R Boo and S Boo | last1=Isles | first1=J. E. | last2=Saw | first2=D. R. B. | journal=Journal of the British Astronomical Association | volume=97 | issue=2 | pages=106–116 | date=February 1987 | bibcode=1987JBAA...97..106I }}</ref>
<ref name=Anderson_Francis_2012>{{cite journal | last1=Anderson | first1=E. | last2=Francis | first2=Ch. | title=XHIP: An extended hipparcos compilation | journal=Astronomy Letters | volume=38 | issue=5 | pages=331 | year=2012 | bibcode=2012AstL...38..331A | arxiv=1108.4971 | doi=10.1134/S1063773712050015 | s2cid=119257644 }}</ref>
<ref name=Anders2021>{{Cite journal |last1=Anders |first1=F. |last2=Khalatyan |first2=A. |last3=Queiroz |first3=A. B. A. |last4=Chiappini |first4=C. |last5=Ardèvol |first5=J. |last6=Casamiquela |first6=L. |last7=Figueras |first7=F. |last8=Jiménez-Arranz |first8=Ó. |last9=Jordi |first9=C. |last10=Monguió |first10=M. |last11=Romero-Gómez |first11=M. |last12=Altamirano |first12=D. |last13=Antoja |first13=T. |last14=Assaad |first14=R. |last15=Cantat-Gaudin |first15=T. |date=2022-02-01 |title=Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G = 18.5 |bibcode=2022A&A...658A..91A |journal=Astronomy and Astrophysics |volume=658 |pages=A91 |doi=10.1051/0004-6361/202142369 |arxiv=2111.01860 |issn=0004-6361}} [https://vizier.cds.unistra.fr/viz-bin/VizieR?-source=I/354 Database] at [[VizieR]]. R Boötis = (Gaia DR3) 1279554668255201152. </ref>
<ref name=Béguin2024>{{Cite journal |last=Béguin |first=E. |last2=Chiavassa |first2=A. |last3=Ahmad |first3=A. |last4=Freytag |first4=B. |last5=Uttenthaler |first5=S. |date=2024-10-01 |title=Retrieving stellar parameters and dynamics of AGB stars with Gaia parallax measurements and CO5BOLD RHD simulations |url=https://www.aanda.org/articles/aa/full_html/2024/10/aa50245-24/aa50245-24.html |journal=Astronomy & Astrophysics |language=en |volume=690 |pages=A125 |doi=10.1051/0004-6361/202450245 |doi-access=free |arxiv=2409.03422 |issn=0004-6361}}</ref>
<ref name=Gontcharov2006>{{cite journal | last1=Gontcharov | first1=G. A. | title=Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system | journal=Astronomy Letters | volume=32| issue=11| pages=759–771| date=November 2006 | bibcode=2006AstL...32..759G | arxiv=1606.08053 | doi = 10.1134/S1063773706110065 | s2cid=119231169 }}</ref>
<ref name=Keenan_et_al_1974>{{cite journal | title=Revised Catalog of Spectra of Mira Variables of Types ME and Se | display-authors=1 | last1=Keenan | first1=Philip C. | last2=Garrison | first2=Robert F. | last3=Deutsch | first3=Armin J. | journal=Astrophysical Journal Supplement | volume=28 | pages=271 | year=1974 | bibcode=1974ApJS...28..271K | doi=10.1086/190318 | doi-access=free }}</ref>
<ref name="AAVSO">{{cite web | url=http://www.aavso.org/vsx/index.php?view=detail.top&oid=4304 | title=R Boötis | author=VSX | date=4 January 2010 | work=AAVSO Website | publisher=[[American Association of Variable Star Observers]] | access-date=26 June 2014 }}</ref>
}}
{{Sky|14|37|11.5787|+|26|44|11.663|2000}} {{Stars of Boötes}}
{{DEFAULTSORT:R Bootis}} [[Category:M-type giants]] [[Category:Mira variables]] [[Category:Emission-line stars]] [[Category:Boötes]] [[Category:Durchmusterung objects]] [[Category:Henry Draper Catalogue objects|128609]] [[Category:Hipparcos objects|071490]] [[Category:Objects with variable star designations|Boötis, R]] [[Category:Asymptotic-giant-branch stars]]