MACHO*05:34:41.3−69:31:39
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Dorado[1] |
| Right ascension | 05h 34m 41.3s |
| Declination | −69° 31′ 39″ |
| Apparent magnitude (V) | 13.54 (-13.89) - 13.91[2] |
| Characteristics | |
| Evolutionary stage | Blue supergiant + Main-sequence |
| Spectral type | O3If* + O6V |
| Variable type | Eclipsing binary[2] |
| Astrometry | |
| Proper motion (μ) | RA: 1.682 mas/yr Dec.: 0.602 mas/yr |
| Distance | 163,000 ly |
| Orbit[2] | |
| Primary | Supergiant star |
| Name | A |
| Period (P) | 1.40474 days |
| Semi-major axis (a) | 22.2 ± 0.2 R⊙ |
| Inclination (i) | 67° ± 1° |
| Semi-amplitude (K2) (secondary) | 263 ± 3 km/s |
| Details[2] | |
| A | |
| Mass | 41 ± 1.2 M☉ |
| Radius | 9.6 ± 0.02 R☉ |
| Temperature | 50,000 K |
| B | |
| Mass | 27 ± 1.2 M☉ |
| Radius | 8.0 ± 0.05 R☉ |
| Temperature | 49,500 K |
| Other designations | |
| MACHO*05:34:41.3−69:31:39, OGLE BRIGHT-LMC-ECL-17, 2MASS J05344134-6931386[3] | |
| Database references | |
| SIMBAD | data |
MACHO*05:34:41.3−69:31:39 is an eclipsing binary star system located in the Large Magellanic Cloud (LMC), within the LH 54 OB association. Comprising two massive early-type O stars, an O3 If* supergiant and an O6 V main-sequence star. It is a rare example of an overcontact binary with a short orbital period. The system is notable for its high stellar masses and strong binary interactions, providing valuable insights into massive star evolution in a low-metallicity environment.[2][4]
Properties
MACHO*05:34:41.3−69:31:39 is an overcontact eclipsing binary with a circular orbit, analyzed using photometric data from the MACHO project and spectroscopic observations. The stars are in an overcontact configuration, filling or exceeding their Roche lobes, which leads to significant interaction and possible mass transfer. The observed masses are lower than those expected for single O3 stars (~100 M⊙), likely due to binary evolution processes.[2][5]
The system exhibits an O'Connell effect in its light curve, with asymmetric maxima and slight variations in eclipse depths, possibly indicating non-equilibrium atmospheres or circumstellar material. Its short orbital period and high masses make it a key target for studying massive binary evolution. The system has been referenced in studies of contact binaries and spectroscopic classifications of early O stars in the LMC.[2]
Significance
As one of the most massive known binaries in the LMC, MACHO*05:34:41.3−69:31:39 offers a unique opportunity to study the evolution of massive stars in a low-metallicity environment, similar to that of the early universe. Its overcontact nature and strong interactions provide constraints for evolutionary models of massive binaries. Further high-resolution spectroscopy and ultraviolet observations have been suggested to refine its parameters and investigate stellar winds or emission features.[6][7][8]
References
- ^ Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
- ^ a b c d e f g Ostrov, P. G. (2001). "Orbital solution for the MACHO*05:34:41.3-69:31:39 O3If*+O6:V eclipsing binary system in the Large Magellanic Cloud". Monthly Notices of the Royal Astronomical Society. 321 (1): L25–L28. arXiv:astro-ph/0009077. Bibcode:2001MNRAS.321L..25O. doi:10.1046/j.1365-8711.2001.04267.x.
- ^ "MACHO*05:34:41.3−69:31:39". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 21 September 2025.
- ^ Ostrov, Pablo G. (2002). "A very massive spectroscopic binary in the LH 54 OB association in the Large Magellanic Cloud". Monthly Notices of the Royal Astronomical Society. 336 (1): 309. arXiv:astro-ph/0205028. Bibcode:2002MNRAS.336..309O. doi:10.1046/j.1365-8711.2002.05754.x.
- ^ Alcock, C.; Allsman, R. A.; Alves, D.; Axelrod, T. S.; Becker, A. C.; Bennett, D. P.; Cook, K. H.; Freeman, K. C.; Griest, K.; Lacy, C. H. S.; Lehner, M. J.; Marshall, S. L.; Minniti, D.; Peterson, B. A.; Pratt, M. R.; Quinn, P. J.; Rodgers, A. W.; Stubbs, C. W.; Sutherland, W.; Welch, D. L. (1997). "The MACHO Project LMC Variable Star Inventory.V.Classification and Orbits of 611 Eclipsing Binary Stars". The Astronomical Journal. 114: 326. Bibcode:1997AJ....114..326A. doi:10.1086/118477.
- ^ Menon, Athira; Langer, Norbert; de Mink, Selma E; Justham, Stephen; Sen, Koushik; Szécsi, Dorottya; de Koter, Alex; Abdul-Masih, Michael; Sana, Hugues; Mahy, Laurent; Marchant, Pablo (2021-09-15). "Detailed evolutionary models of massive contact binaries – I. Model grids and synthetic populations for the Magellanic Clouds". Monthly Notices of the Royal Astronomical Society. 507 (4): 5013–5033. arXiv:2011.13459. doi:10.1093/mnras/stab2276. ISSN 0035-8711.
- ^ Neßlinger, Stefan Rainer (2007). Photometric and spectroscopic analysis of extragalactic early-type eclipsing binaries (Thesis). Bibcode:2007PhDT.......133N.
- ^ Walborn, Nolan R.; Howarth, Ian D.; Lennon, Daniel J.; Massey, Philip; Oey, M. S.; Moffat, Anthony F. J.; Skalkowski, Gwen; Morrell, Nidia I.; Drissen, Laurent; Parker, Joel Wm. (2002). "A New Spectral Classification System for the Earliest O Stars: Definition of Type O2". The Astronomical Journal. 123 (5): 2754. Bibcode:2002AJ....123.2754W. doi:10.1086/339831.