| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 17 19 05.548 |
| Declination | −29° 43′ 41.1989″ |
| Apparent magnitude (V) | 11.44 |
| Characteristics | |
| Spectral type | O4.5Ifpe |
| U−B color index | +0.37 |
| B−V color index | +1.49 |
| V−R color index | +1.28 |
| Astrometry | |
| Radial velocity (Rv) | −51.0 km/s |
| Proper motion (μ) | RA: −2.5 mas/yr Dec.: −6.6 mas/yr |
| Distance | 9,500–12,700 ly (2,900–3,900 pc) |
| Absolute magnitude (MV) | −6.335 |
| Details | |
| Mass | 120 M☉ |
| Radius | 18.65 R☉ |
| Luminosity | 802,000 L☉ |
| Surface gravity (log g) | 3.61 cgs |
| Temperature | 40,000 K |
| Rotational velocity (v sin i) | <107 km/s |
| Age | 1.10 Myr |
| Other designations | |
| LS 4067, CD−38°11748, Hen 3-1374, HM 1 VB 4, TYC 7870-896-1, 2MASS J17190554-3848496 | |
| Database references | |
| SIMBAD | data |
LSS 4067, also known as CD−38°11748, is an O-type blue supergiant star located in the constellation Scorpius, very close to the galactic plane. It is part of the open cluster HM 1, although its distance is not well known; it may be anywhere between 9,500 and 12,700 light years (2900 to 3900 parsecs) away from the Earth. Despite being a blue supergiant, it is extremely reddened by interstellar extinction, so its apparent magnitude is brighter for longer-wavelength passbands. Without the extinction, it is estimated that LS 4067 would be 5.8 magnitudes brighter, a naked eye star with an apparent magnitude of 5.3.
Although the Gaia Data Release 2 parallax for LS 4067 is negative, a likely distance can be calculated from it. The star is thought to be between 8,202 and 14,084 pc away, statistically most likely at 10,170 pc. It was catalogued as a member of the faint cluster Havlen-Moffat No. 1, but is no longer thought to be a member. The cluster lies about 3,300 pc.
LSS 4067 has an absolute bolometric magnitude of −11.4, making it one of the most luminous stars known. Indeed, many of the hottest and most luminous stars known are O-type supergiants, or Wolf-Rayet stars. LSS 4067 has an unusual spectrum, with various emission lines including N III and He II emission lines, thus the "f" in its spectral type. Because of this unusual spectrum, classifying the star or deducing its properties has proved relatively difficult: for example, the effective temperature is predicted to be too cool and the surface gravity too high.
See also
References
- ^ Cutri, Roc M.; Skrutskie, Michael F.; Van Dyk, Schuyler D.; Beichman, Charles A.; Carpenter, John M.; Chester, Thomas; Cambresy, Laurent; Evans, Tracey E.; Fowler, John W.; Gizis, John E.; Howard, Elizabeth V.; Huchra, John P.; Jarrett, Thomas H.; Kopan, Eugene L.; Kirkpatrick, J. Davy; Light, Robert M.; Marsh, Kenneth A.; McCallon, Howard L.; Schneider, Stephen E.; Stiening, Rae; Sykes, Matthew J.; Weinberg, Martin D.; Wheaton, William A.; Wheelock, Sherry L.; Zacarias, N. (2003). "VizieR Online Data Catalog: 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)". CDS/ADC Collection of Electronic Catalogues. 2246: II/246. Bibcode:2003yCat.2246....0C.
- ^ Vázquez, R. A.; Baume, G. (2001). "The open cluster Havlen-Moffat No. 1 revisited". Astronomy and Astrophysics. 371 (3): 908–920. Bibcode:2001A&A...371..908V. doi:10.1051/0004-6361:20010410.
- Sota, A.; et al. (2014). "The Galactic O-Star Spectroscopic Survey (GOSSS). II. Bright Southern Stars". The Astrophysical Journal Supplement. 211 (1): 10. arXiv:1312.6222. Bibcode:2014ApJS..211...10S. doi:10.1088/0067-0049/211/1/10. S2CID 118847528.
- ^ Williams, S. J.; et al. (2011). "Radial Velocities of Galactic O-type Stars. I. Short-term Constant Velocity Stars". The Astronomical Journal. 142 (5): 146. Bibcode:2011AJ....142..146W. doi:10.1088/0004-6256/142/5/146.
- ^ Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27 – L30. Bibcode:2000A&A...355L..27H.
- ^ Nebot Gómez-Morán, A.; Oskinova, L. M. (2018). "The X-ray catalog of spectroscopically identified Galactic O stars. Investigating the dependence of X-ray luminosity on stellar and wind parameters". Astronomy and Astrophysics. 620: A89. arXiv:1808.07880. Bibcode:2018A&A...620A..89N. doi:10.1051/0004-6361/201833453. S2CID 73607059.
- ^ Massey, P.; Degioia-Eastwood, K.; Waterhouse, E. (2001). "The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables Determined from Cluster Turnoffs. II. Results from 12 Galactic Clusters and OB Associations". The Astronomical Journal. 121 (2): 1050–1070. arXiv:astro-ph/0010654. Bibcode:2001AJ....121.1050M. doi:10.1086/318769. S2CID 53345173.
- "CD-38 11748". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 19 January 2016.
- Maíz Apellániz, J.; Barbá, R. H. (2018). "Optical-NIR dust extinction towards Galactic O stars". Astronomy and Astrophysics. 613: A9. arXiv:1712.09228. Bibcode:2018A&A...613A...9M. doi:10.1051/0004-6361/201732050. S2CID 119342685.
- Bailer-Jones, C. A. L.; Rybizki, J.; Fouesneau, M.; Mantelet, G.; Andrae, R. (2018). "Estimating Distance from Parallaxes. IV. Distances to 1.33 Billion Stars in Gaia Data Release 2". The Astronomical Journal. 156 (2): 58. arXiv:1804.10121. Bibcode:2018AJ....156...58B. doi:10.3847/1538-3881/aacb21. S2CID 119289017.
