Star in the constellation Musca
S Muscae
Location of S Muscae (circled)
Observation dataEpoch J2000 Equinox J2000
Constellation
Musca
Right ascension 12h 12m 47.01834s [ 1]
Declination
−70° 09′ 06.4363″[ 1]
Apparent magnitude (V)6.394[ 2] (5.89 - 6.49[ 3]
Characteristics
Spectral type
F6Ib (F6-G0[ 3] [ 4]
U−B color index
+0.66[ 5]
B−V color index
+1.00[ 5]
Variable type
δ Cepheid [ 3]
Astrometry Radial velocity (Rv )−1.91[ 6] km/s Proper motion (μ) RA: −7.79[ 1] mas /yr Dec.: −0.60[ 1] mas /yr Parallax (π)1.99± 0.84 mas [ 1] Distance 863[ 2] pc Absolute magnitude (MV )−4.01[ 7] Orbit [ 7] [ 8] Period (P)504.9 ± 0.07 Semi-major axis (a)794 AU Eccentricity (e)0.08 ± 0.002 Inclination (i)32 ± 1° Semi-amplitude 1 )14.7 ± 0.2 km/s Details Mass 6.2[ 7] M ☉ Radius 65.1[ 2] R ☉ Luminosity 3,467[ 7] L ☉ Metallicity +0.18[ 9] companion Mass 5.3[ 7] M ☉ Temperature 17,000[ 10] K Other designations S Mus, HR 4645, SAO 251791, CD −69°977, GSC 09231-00752, HD 106111, GC 16679, HIP 59551, AAVSO 1207-69Database references SIMBAD data
S Muscae is a classical (δ) Cepheid variable star in the constellation Musca about 2,600 light years away.
A light curve for S Muscae, plotted from TESS [ 11] 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.[ 3] 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,[ 12] [ 13]
S Muscae has been found to lie within the faint star cluster ASCC 69.[ 14]
References
^ a b c d e Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics . 474 (2): 653– 664. arXiv :0708.1752 Bibcode :2007A&A...474..653V . doi :10.1051/0004-6361:20078357 . S2CID 18759600 . ^ a b c Moskalik, P.; Gorynya, N. A. (2005). "Mean Angular Diameters and Angular Diameter Amplitudes of Bright Cepheids". Acta Astronomica . 55 : 247. arXiv :astro-ph/0507076 Bibcode :2005AcA....55..247M . ^ a b c d Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S . 1 . Bibcode :2009yCat....102025S . ^ Skiff, B. A. (2014). "VizieR Online Data Catalog: Catalogue of Stellar Spectral Classifications (Skiff, 2009-2014)". VizieR On-line Data Catalog: B/Mk. Originally Published in: Lowell Observatory (October 2014) . 1 . Bibcode :2014yCat....1.2023S . ^ a b Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues . 2237 . Bibcode :2002yCat.2237....0D . ^ Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; Levato, H.; Morrell, N. I.; Torres, G.; Udry, S. (2004). "SB9: The ninth catalogue of spectroscopic binary orbits". Astronomy and Astrophysics . 424 (2): 727– 732. arXiv :astro-ph/0406573 Bibcode :2004A&A...424..727P . doi :10.1051/0004-6361:20041213 . S2CID 119387088 . ^ a b c d e Remage Evans, Nancy; Bond, Howard E.; Schaefer, Gail H.; Mason, Brian D.; Karovska, Margarita; Tingle, Evan (2013). "Binary Cepheids: Separations and Mass Ratios in 5 M ⊙ Binaries". The Astronomical Journal . 146 (4): 93. arXiv :1307.7123 Bibcode :2013AJ....146...93E . doi :10.1088/0004-6256/146/4/93 . S2CID 34133110 . ^ Petterson, O. K. L.; Cottrell, P. L.; Albrow, M. D. (2004). "The orbits of southern binary Cepheids" . Monthly Notices of the Royal Astronomical Society . 350 (1): 95– 112. Bibcode :2004MNRAS.350...95P . doi :10.1111/j.1365-2966.2004.07555.x ^ Klagyivik, P.; Szabados, L. (2009). "Observational studies of Cepheid amplitudes. I. Period-amplitude relationships for Galactic Cepheids and interrelation of amplitudes". Astronomy and Astrophysics . 504 (3): 959. arXiv :0908.3561 Bibcode :2009A&A...504..959K . doi :10.1051/0004-6361/200811464 . S2CID 18283579 . ^ Evans, Nancy Remage; Massa, Derck; Fullerton, Alexander; Sonneborn, George; Iping, Rosina (2006). "Cepheid Masses: FUSE Observations of S Muscae". The Astrophysical Journal . 647 (2): 1387– 1392. arXiv :astro-ph/0607489 Bibcode :2006ApJ...647.1387E . doi :10.1086/505519 . S2CID 119020617 . ^ "MAST: Barbara A. Mikulski Archive for Space Telescopes" . Space Telescope Science Institute. Retrieved 8 December 2021 .^ Bohm-Vitense, Erika; Remage Evans, Nancy; Carpenter, Kenneth; Beck-Winchatz, Bernhard; et al. (1997). "The Mass of the Classical Cepheid S Muscae" . The Astrophysical Journal . 477 (2): 916. Bibcode :1997ApJ...477..916B . doi :10.1086/303725 ^ Evans, Nancy Remage (1990). "The orbit and colors of the Cepheid S MUSCAE" . Publications of the Astronomical Society of the Pacific . 102 : 551. Bibcode :1990PASP..102..551E . doi :10.1086/132668 ^ Remage Evans, Nancy; Pillitteri, Ignazio; Wolk, Scott; Guinan, Edward; Engle, Scott; Bond, Howard E.; Schaefer, Gail H.; Karovska, Margarita; Depasquale, Joseph; Tingle, Evan (2014). "X-Ray Detection of the Cluster Containing the Cepheid S Mus". The Astrophysical Journal Letters . 785 (2): L25. arXiv :1403.6939 Bibcode :2014ApJ...785L..25E . doi :10.1088/2041-8205/785/2/L25 . S2CID 119113620 .
