  | |
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Musca |
| Right ascension | 12h 12m 47.01834s1 |
| Declination | −70° 09′ 06.4363″1 |
| Apparent magnitude (V) | 5.89 - 6.492 |
| Characteristics | |
| Spectral type | F6Ib (F6-G02) + B5V3 |
| U−B color index | +0.664 |
| B−V color index | +1.004 |
| Variable type | δ Cepheid2 |
| Astrometry | |
| Radial velocity (Rv) | −1.915 km/s |
| Proper motion (μ) | RA: −7.791 mas/yr Dec.: −0.601 mas/yr |
| Parallax (π) | 1.99±0.84 mas1 |
| Distance | 2,798 ± 55 ly (858±17 pc)6 |
| Absolute magnitude (MV) | −4.017 |
| Orbit6 | |
| Period (P) | 506.3±0.5 days |
| Semi-major axis (a) | (2.95±0.09)×10−3" (2.53±0.09 AU) |
| Eccentricity (e) | 0.088±0.006 |
| Inclination (i) | 144.7±2.8° |
| Longitude of the node (Ω) | 99.6±14.4° |
| Periastron epoch (T) | 2,457,165.9±4.4 JD |
| Argument of periastron (ω) (secondary) | 194.8±3.3° |
| Semi-amplitude (K1) (primary) | 14.85±0.03 km/s |
| Semi-amplitude (K2) (secondary) | 16.63±3.27 km/s |
| Details | |
| S Mus A | |
| Mass | 4.44±0.916 M☉ |
| Radius | 65.18 R☉ |
| Luminosity | 3,4677 L☉ |
| Metallicity | +0.189 |
| S Mus B | |
| Mass | 3.98±0.216 M☉ |
| Temperature | 17,00010 K |
| Other designations | |
| S Mus, HR 4645, SAO 251791, CD−69°977, GSC 09231-00752, HD 106111, GC 16679, HIP 59551, AAVSO 1207-69 | |
| Database references | |
| SIMBAD | data |
S Muscae is a classical (δ) Cepheid variable star in the constellation Musca about 2,800 light years away.
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.2 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,12 one of the hottest and brightest companions of a Cepheid known. The two stars orbit each other every 505 days.13
S Muscae has been found to lie within the faint star cluster ASCC 69.14
References
References
- 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.
- 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.
- 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.
- Gallenne, A.; Kervella, P.; Borgniet, S.; Mérand, A.; Pietrzyński, G.; Gieren, W.; Monnier, J. D.; Schaefer, G. H.; Evans, N. R.; Anderson, R. I.; Baron, F.; Roettenbacher, R. M.; Karczmarek, P. (February 2019). "Multiplicity of Galactic Cepheids from long-baseline interferometry. IV. New detected companions from MIRC and PIONIER observations". Astronomy and Astrophysics. 622: A164. Bibcode:2019A&A...622A.164G. doi:10.1051/0004-6361/201834614. ISSN 0004-6361.
- 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.
- 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.
- 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.