{{Short description|Star in the constellation Musca}} {{Starbox begin}} {{Starbox image | image= {{Location mark |image=Musca constellation map.svg|alt=|float=center|width=280 |label=|position=right |mark=Red circle.svg|mark_width=8|mark_link=S Mus|x=576|y=406 }} |caption=Location of S Muscae (circled) }} {{Starbox observe | epoch=J2000 | ra={{RA|12|12|47.01834}}<ref name=hipparcos>{{cite journal|bibcode=2007A&A...474..653V|title=Validation of the new Hipparcos reduction|journal=Astronomy and Astrophysics|volume=474|issue=2|pages=653–664|last1=Van Leeuwen|first1=F.|year=2007|doi=10.1051/0004-6361:20078357|arxiv = 0708.1752 |s2cid=18759600}}</ref> | dec={{DEC|−70|09|06.4363}}<ref name=hipparcos/> | appmag_v=5.89 - 6.49<ref name=gcvs/> |constell= [[Musca (constellation)|Musca]] }} {{Starbox character | class={{nowrap|F6Ib (F6-G0<ref name=gcvs/>) + B5V<ref name=skiff>{{cite journal|bibcode=2014yCat....1.2023S|title=VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2014)|journal=VizieR On-line Data Catalog: B/Mk. Originally Published in: Lowell Observatory (October 2014)|volume=1|last1=Skiff|first1=B. A.|year=2014}}</ref>}} | b-v=+1.00<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|last1=Ducati|first1=J. R.|year=2002}}</ref> | u-b=+0.66<ref name=ducati/> | variable=[[Classical Cepheid variable|δ Cepheid]]<ref name=gcvs/> }} {{Starbox astrometry | radial_v=−1.91<ref>{{cite journal|bibcode=2004A&A...424..727P|title=SB9: The ninth catalogue of spectroscopic binary orbits|journal=Astronomy and Astrophysics|volume=424|issue=2|pages=727–732|last1=Pourbaix|first1=D.|last2=Tokovinin|first2=A. A.|last3=Batten|first3=A. H.|last4=Fekel|first4=F. C.|last5=Hartkopf|first5=W. I.|last6=Levato|first6=H.|last7=Morrell|first7=N. I.|last8=Torres|first8=G.|last9=Udry|first9=S.|year=2004|doi=10.1051/0004-6361:20041213|arxiv = astro-ph/0406573 |s2cid=119387088}}</ref> | prop_mo_ra=−7.79<ref name=hipparcos/> | prop_mo_dec=−0.60<ref name=hipparcos/> | parallax=1.99 | p_error=0.84 | parallax_footnote=<ref name=hipparcos/> | dist_pc={{Val|858|17}} | dist_ly={{convert|858|±|17|pc|ly|disp=number}} | dist_footnote=<ref name=Gallene2019/> | absmag_v=−4.01<ref name=evans13>{{cite journal|bibcode=2013AJ....146...93E|arxiv=1307.7123|title=Binary Cepheids: Separations and Mass Ratios in 5 M ⊙ Binaries|journal=The Astronomical Journal|volume=146|issue=4|pages=93|last1=Remage Evans|first1=Nancy|last2=Bond|first2=Howard E.|last3=Schaefer|first3=Gail H.|last4=Mason|first4=Brian D.|last5=Karovska|first5=Margarita|last6=Tingle|first6=Evan|year=2013|doi=10.1088/0004-6256/146/4/93|s2cid=34133110}}</ref> }} {{Starbox orbit | reference = <ref name=Gallene2019>{{Cite journal |last=Gallenne |first=A. |last2=Kervella |first2=P. |last3=Borgniet |first3=S. |last4=Mérand |first4=A. |last5=Pietrzyński |first5=G. |last6=Gieren |first6=W. |last7=Monnier |first7=J. D. |last8=Schaefer |first8=G. H. |last9=Evans |first9=N. R. |last10=Anderson |first10=R. I. |last11=Baron |first11=F. |last12=Roettenbacher |first12=R. M. |last13=Karczmarek |first13=P. |date=February 2019 |title=Multiplicity of Galactic Cepheids from long-baseline interferometry. IV. New detected companions from MIRC and PIONIER observations |bibcode=2019A&A...622A.164G |journal=Astronomy and Astrophysics |language=en |volume=622 |pages=A164 |doi=10.1051/0004-6361/201834614 |issn=0004-6361}}</ref> | period_unitless = {{val|506.3|0.5}} days | axis = {{Val|2.95|0.09|e=-3}} | axis_unitless = {{val|2.53|0.09|ul=AU}} | eccentricity = {{val|0.088|0.006}} | inclination = {{val|144.7|2.8}} | node = {{Val|99.6|14.4}} | periastron = {{Val|fmt=commas|2457165.9|4.4|ul=JD}} | periarg = {{Val|194.8|3.3}} | k1 = {{val|14.85|0.03}} | k2 = {{Val|16.63|3.27}} }} {{Starbox detail | component1=S Mus A | mass={{Val|4.44|0.91}}<ref name=Gallene2019/> | radius=65.1<ref name=moskalik>{{cite journal|bibcode=2005AcA....55..247M|arxiv=astro-ph/0507076|title=Mean Angular Diameters and Angular Diameter Amplitudes of Bright Cepheids|journal=Acta Astronomica|volume=55|pages=247|last1=Moskalik|first1=P.|last2=Gorynya|first2=N. A.|year=2005}}</ref> | luminosity=3,467<ref name=evans13/> | temperature= | metal=+0.18<ref>{{cite journal|bibcode= 2009A&A...504..959K|title= Observational studies of Cepheid amplitudes. I. Period-amplitude relationships for Galactic Cepheids and interrelation of amplitudes|journal= Astronomy and Astrophysics|volume= 504|issue= 3|pages= 959|last1= Klagyivik|first1= P.|last2= Szabados|first2= L.|year= 2009|doi= 10.1051/0004-6361/200811464|arxiv = 0908.3561 |s2cid= 18283579}}</ref> | rotation= | component2=S Mus B | mass2={{val|3.98|0.21}}<ref name=Gallene2019/> | temperature2=17,000<ref name=evans06>{{cite journal|bibcode=2006ApJ...647.1387E|arxiv=astro-ph/0607489|title=Cepheid Masses: FUSE Observations of S Muscae|journal=The Astrophysical Journal|volume=647|issue=2|pages=1387–1392|last1=Evans|first1=Nancy Remage|last2=Massa|first2=Derck|last3=Fullerton|first3=Alexander|last4=Sonneborn|first4=George|last5=Iping|first5=Rosina|year=2006|doi=10.1086/505519|s2cid=119020617}}</ref> | age_myr2= }} {{Starbox catalog | names= [[Variable star designation|S]] Mus, [[Bright Star Catalogue|HR]] 4645, [[Smithsonian Astrophysical Observatory Star Catalog|SAO]] 251791, [[Durchmusterung|CD]]−69°977, [[Guide Star Catalog|GSC]] 09231-00752, [[Henry Draper Catalogue|HD]] 106111, [[Boss General Catalogue|GC]] 16679, [[Hipparcos catalogue|HIP]] 59551, [[AAVSO]] 1207-69 }} {{Starbox reference |Simbad=S+Muscae }} {{Starbox end}}
'''S Muscae''' is a [[Classical Cepheid variable|classical (δ) Cepheid]] [[variable star]] in the [[constellation]] [[Musca (constellation)|Musca]] about 2,800 light years away.
[[File:SMusLightCurve.png|thumb|left|A [[light curve]] for S Muscae, plotted from ''[[Transiting Exoplanet Survey Satellite|TESS]]'' data<ref name=MAST/>]] S Muscae is a [[yellow supergiant]] ranging between spectral types F6Ib and G0Ib and magnitudes 5.89 to 6.49 over a period of 9.66 days.<ref name=gcvs>{{cite journal|bibcode=2009yCat....102025S|title=VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)|journal=VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S|volume=1|display-authors=etal|last1=Samus|first1=N. N.|last2=Durlevich|first2=O. V.|year=2009}}</ref> It is a luminous star around six times as massive as the Sun and 65.1 times the radius of the Sun. It is a [[binary star]] with a blue-white [[main sequence]] star companion likely to be of spectral type B3V to B5V with a mass of just over five solar masses,<ref name="bohm97">{{cite journal|display-authors=4|bibcode = 1997ApJ...477..916B|doi=10.1086/303725|title = The Mass of the Classical Cepheid S Muscae|journal = The Astrophysical Journal|volume = 477|issue = 2|pages = 916|year = 1997|last1 = Bohm-Vitense|first1 = Erika|last2 = Remage Evans|first2 = Nancy|last3 = Carpenter|first3 = Kenneth|last4 = Beck-Winchatz|first4 = Bernhard|last5 = Robinson|first5 = Richard|doi-access = free}}</ref> one of the hottest and brightest companions of a Cepheid known. The two stars orbit each other every 505 days.<ref>{{cite journal|bibcode=1990PASP..102..551E|doi=10.1086/132668|title=The orbit and colors of the Cepheid S MUSCAE|journal=Publications of the Astronomical Society of the Pacific|volume=102|pages=551|year=1990|last1=Evans|first1=Nancy Remage|doi-access=free}}</ref>
S Muscae has been found to lie within the faint star cluster ASCC 69.<ref>{{cite journal|bibcode=2014ApJ...785L..25E|arxiv=1403.6939|title=X-Ray Detection of the Cluster Containing the Cepheid S Mus|journal=The Astrophysical Journal Letters|volume=785|issue=2|pages=L25|last1=Remage Evans|first1=Nancy|last2=Pillitteri|first2=Ignazio|last3=Wolk|first3=Scott|last4=Guinan|first4=Edward|last5=Engle|first5=Scott|last6=Bond|first6=Howard E.|last7=Schaefer|first7=Gail H.|last8=Karovska|first8=Margarita|last9=Depasquale|first9=Joseph|last10=Tingle|first10=Evan|year=2014|doi=10.1088/2041-8205/785/2/L25|s2cid=119113620}}</ref> {{clear left}}
==References== <references>
<ref name=MAST>{{cite web |title=MAST: Barbara A. Mikulski Archive for Space Telescopes |url=https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html |publisher=Space Telescope Science Institute |access-date=8 December 2021}}</ref>
</references>
{{Musca}}
[[Category:Musca]] [[Category:Classical Cepheid variables]] [[Category:Objects with variable star designations|Muscae, S]] [[Category:Bright Star Catalogue objects|4645]] [[Category:Henry Draper Catalogue objects|106111]] [[Category:Hipparcos objects|059551]] [[Category:Durchmusterung objects|CD-69 00977]] [[Category:Binary stars]] [[Category:Population I stars]] [[Category:F-type supergiants]] [[Category:B-type main-sequence stars]]