Lambda Muscae, Latinized from λ Muscae, and often catalogued HD 102249 or HIP 57363, is a triple star system and the fourth-brightest star in the Southern Hemisphere constellation of Musca (the Fly). Lambda Muscae visibly makes up the far end of the tail of the visual Musca constellation. It is one of the stars catalogued in astronomer Johann Bayer's 1603 publications Uranometria.
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Musca |
| Right ascension | 11h 45m 36.41916s[1] |
| Declination | −66° 43′ 43.5440″[1] |
| Apparent magnitude (V) | +3.63[2] |
| Characteristics | |
| Spectral type | A7 V[3] |
| U−B color index | +0.14[2] |
| B−V color index | +0.16[2] |
| R−I color index | 0.08 |
| Astrometry | |
| Radial velocity (Rv) | +15.0±0.3[4] km/s |
| Proper motion (μ) | RA: −100.35[1] mas/yr Dec.: +33.49[1] mas/yr |
| Parallax (π) | 25.65 ± 0.34 mas[1] |
| Distance | 127 ± 2 ly (39.0 ± 0.5 pc) |
| Absolute magnitude (MV) | +1.07[5] |
| Details[6] | |
| Aa | |
| Mass | 2.28 M☉ |
| Radius | 3.7 R☉ |
| Luminosity | 40[7] L☉ |
| Surface gravity (log g) | 3.87[8] cgs |
| Temperature | 7,700 K |
| Rotational velocity (v sin i) | 57.7±1.7[5] km/s |
| Age | 700 Myr |
| Ab | |
| Mass | 0.43 M☉ |
| C | |
| Mass | 0.16 M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
Distance and visibility
editBased on research done by the European Space Agency for the Hipparcos Star Catalogue, Lambda Muscae exhibits a parallax of 25.42 milliarcseconds.[9] With this data it can be calculated that Lambda Muscae is situated at a distance of 39.3 parsecs, or 128.0 light years, away from the sun.
Lambda Muscae is a star of the third magnitude (or 3.68(v) to be exact) when viewed from the Earth, and is visible to the naked eye in regions that lack dense light pollution.
Lambda Muscae is the farthest right star in the visual constellation of Musca and is thus the tail of the fly.
Stellar characteristics
editThe primary component has a listed spectral type of A7V.[10] The A7 portion of this designation that Lambda Muscae Aa is a class A7 star, meaning the light it emits is bluish-white in color and burns at a temperature significantly hotter than the Sun, which is a G2 star. A7 stars are on the larger end of the Harvard spectral classification list, being only smaller and dimmer than Class-O and Class-B stars.
The other components of the system are red dwarfs. They are separated by the primary by 1.65 and 6.4 astronomical units respectively.[6]
References
edit- ^ 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 Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.
- ^ Gray, R. O.; et al. (2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal, 132 (1): 161–70, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- ^ a b Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics, 542: A116, arXiv:1204.2459, Bibcode:2012A&A...542A.116A, doi:10.1051/0004-6361/201118724, S2CID 53666672.
- ^ a b Waisberg, Idel; Klein, Ygal; Katz, Boaz (2024-08-01). "Hidden Companions to Intermediate-mass Stars. XXII. Inferring a 0.43M☉, 1.65 au Companion in the Astrometric Binary within the Triple System Lambda Muscae". Research Notes of the American Astronomical Society. 8 (8): 206. Bibcode:2024RNAAS...8..206W. doi:10.3847/2515-5172/ad713a. ISSN 2515-5172.
- ^ McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
- ^ David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ "HIP 57363". The Hipparcos and Tycho Catalogues. ESA. 1997. Retrieved 21 December 2008.
- ^ "* lam Mus". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 21 December 2008.