  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ophiuchus |
| Right ascension | 18h 00m 15.79825s [1] |
| Declination | 04° 22′ 07.0163″ [1] |
| Apparent magnitude (V) | 4.60 [2] |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | B2Ve [3] |
| U−B color index | −0.81 [2] |
| B−V color index | −0.02 [2] |
| Variable type | γ Cas [4] |
| Astrometry | |
| Radial velocity (Rv) | −12.80 [5] km/s |
| Proper motion (μ) |
RA: +1.23
[1]
mas/
yr Dec.: −12.73 [1] mas/ yr |
| Parallax (π) | 5.01 ± 0.26 mas [1] |
| Distance | 650 ± 30
ly (200 ± 10 pc) |
| Absolute magnitude (MV) | −2.8 + −0.2 [6] |
| Orbit [6] | |
| Period (P) | 23421.1 ± 4.1 d |
| Semi-major axis (a) | 178.36 ± 1.37 mas |
| Eccentricity (e) | 0.142 ± 0.006 |
| Inclination (i) | 75.90 ± 0.69° |
| Longitude of the node (Ω) | 338.87 ± 0.31° |
| Periastron epoch (T) | JD 2452658.5 ± 50.2 |
|
Argument of periastron (ω) (secondary) | 115.24 ± 0.95° |
| Details | |
| 66 Oph A | |
| Mass | 9.6 [6] M☉ |
| Luminosity | 1524.63 [7] L☉ |
| Surface gravity (log g) | 3.69 [8] cgs |
| Temperature | 22,000 [9] K |
| Metallicity [Fe/H] | 0.00 [8] dex |
| Rotational velocity (v sin i) | 250 [10] km/s |
| Age | 14.0±3.2 [11] Myr |
| 66 Oph B | |
| Mass | 3.8 [6] M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
66 Ophiuchi is a binary [6] variable star [13] in the equatorial constellation of Ophiuchus. It has the variable star designation V2048 Ophiuchi, while 66 Ophiuchi is the Flamsteed designation. This object is visible to the naked eye as a faint, blue-white hued point of light with a baseline apparent visual magnitude of 4.60. [2] It is located approximately 650 light years away from the Sun based on parallax, [1] but is drifting closer with a radial velocity of −13 km/s. [5] The star has a peculiar velocity of 13.1±3.2 km/s [14] relative to its neighbors.
The primary star, known as 66 Ophiuchi A, is a main sequence Be star with a stellar classification of B2Ve. [3] Be stars are rapidly rotating stars that eject gas from their equators due to their rotation, forming disks that produce emission lines. 66 Ophiuchi A's disk extends out to 115 R☉. [15] Like many other Be stars, it is a γ Cas variable; a shell star with a circumstellar disc of gas and is exhibiting irregular changes in brightness, ranging from 4.85 up to 4.55 magnitude. [4] The star is 14 million years old with 9.6 [6] times the Sun's mass and is spinning rapidly with a projected rotational velocity of 250 km/s. [10] It is radiating 1,525 [7] times the Sun's luminosity from its photosphere at an effective temperature of 22,000 K. [9] Because of its rotation, it has a polar equatorial radius 4.50 that of the Sun, but an equatorial radius 5.11 that of the Sun. [15]
A magnitude 6.5 visual companion at an angular separation of 0.1 ″ has been reported, and is known as 66 Ophiuchi B. [16] It is 2.61 magnitudes fainter than the primary. This corresponds to a mass of about 3.8 times that of the Sun, and a spectral class of about B8. [6]
References
- ^ a b c d e f 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. Vizier catalog entry
- ^ a b c d 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.
- ^ a b Hoffleit, D.; Warren, W. H. (1995). "VizieR Online Data Catalog: Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)". VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H. 5050. Bibcode: 1995yCat.5050....0H.
- ^ a b 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.
- ^ a b Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv: 1606.08053. Bibcode: 2006AstL...32..759G. doi: 10.1134/S1063773706110065. S2CID 119231169.
- ^ a b c d e f g Hutter, D. J.; Tycner, C.; Zavala, R. T.; Benson, J. A.; Hummel, C. A.; Zirm, H. (2021). "Surveying the Bright Stars by Optical Interferometry. III. A Magnitude-limited Multiplicity Survey of Classical Be Stars". The Astrophysical Journal Supplement Series. 257 (2): 69. arXiv: 2109.06839. Bibcode: 2021ApJS..257...69H. doi: 10.3847/1538-4365/ac23cb. S2CID 237503492.
- ^ a b Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971. Bibcode: 2012AstL...38..331A. doi: 10.1134/S1063773712050015. S2CID 119257644. Vizier catalog entry
- ^ a b Wu, Yue; Singh, H. P.; Prugniel, P.; Gupta, R.; Koleva, M. (2010). "Coudé-feed stellar spectral library – atmospheric parameters". Astronomy & Astrophysics. 525: A71. arXiv: 1009.1491. Bibcode: 2011A&A...525A..71W. doi: 10.1051/0004-6361/201015014. S2CID 53480665.
- ^ a b Hohle, M.M.; Neuhäuser, R.; Schutz, B.F. (2010). "Masses and luminosities of O- and B-type stars and red supergiants". Astronomische Nachrichten. 331 (4): 349. arXiv: 1003.2335. Bibcode: 2010AN....331..349H. doi: 10.1002/asna.200911355. S2CID 111387483. Vizier catalog entry
- ^ a b Abt, Helmut A.; Levato, Hugo; Grosso, Monica (2002). "Rotational Velocities of B Stars". The Astrophysical Journal. 573 (1): 359–365. Bibcode: 2002ApJ...573..359A. doi: 10.1086/340590.
- ^ Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (2011). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1): 190–200. arXiv: 1007.4883. Bibcode: 2011MNRAS.410..190T. doi: 10.1111/j.1365-2966.2010.17434.x. S2CID 118629873. Vizier catalog entry
- ^ "66 Oph". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-21.
- ^ a b Floquet, M.; et al. (October 2002). "Variability and pulsations in the Be star 66 Ophiuchi" (PDF). Astronomy and Astrophysics. 394: 137–149. Bibcode: 2002A&A...394..137F. doi: 10.1051/0004-6361:20021105.
- ^ Bobylev, V. V.; Bajkova, A. T. (August 2013). "Galactic kinematics from a sample of young massive stars". Astronomy Letters. 39 (8): 532–549. arXiv: 1307.1677. Bibcode: 2013AstL...39..532B. doi: 10.1134/S106377371308001X. S2CID 118568203.
- ^ a b Marr, K. C.; Jones, C. E.; Carciofi, A. C.; Rubio, A. C.; Mota, B. C.; Ghoreyshi, M. R.; Hatfield, D. W.; Rímulo, L. R. (2021). "The be Star 66 Ophiuchi: 60 Years of Disk Evolution". The Astrophysical Journal. 912 (1): 76. arXiv: 2103.06948. Bibcode: 2021ApJ...912...76M. doi: 10.3847/1538-4357/abed4c. ISSN 0004-637X. S2CID 232223272.
- ^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode: 2001AJ....122.3466M. doi: 10.1086/323920. Vizier catalog entry
