HD 69863 is a binary star[11] system in the southern constellation of Carina. It is visible to the naked eye as a dim point of light with a combined apparent visual magnitude of 5.16.[6] The system is located at a distance of about255 light years from the Sun based on parallax.[1][3] The dual nature of this system was announced in 1832 by German astronomer Carl Rümker.[12] As of 2015, the pair had an angular separation of 4.10″ along a position angle of 70°.[2]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Carina |
| A | |
| Right ascension | 08h 15m 16.42864s[1] |
| Declination | −62° 54′ 56.5007″[1] |
| Apparent magnitude (V) | 5.27[2] |
| B | |
| Right ascension | 08h 15m 16.47622s[3] |
| Declination | −62° 54′ 54.8700″[3] |
| Apparent magnitude (V) | 7.62[2] |
| Characteristics | |
| Spectral type | A2V[4] + F2V[5] |
| B−V color index | 0.086±0.003[6] |
| Astrometry | |
| Radial velocity (Rv) | 4.0±3.7[6] km/s |
| Absolute magnitude (MV) | 0.71[6] |
| A | |
| Proper motion (μ) | RA: −26.674[1] mas/yr Dec.: -12.060[1] mas/yr |
| Parallax (π) | 12.5410 ± 0.1714 mas[1] |
| Distance | 260 ± 4 ly (80 ± 1 pc) |
| B | |
| Proper motion (μ) | RA: −20.911[3] mas/yr Dec.: -14.466[3] mas/yr |
| Parallax (π) | 12.7714 ± 0.0329 mas[3] |
| Distance | 255.4 ± 0.7 ly (78.3 ± 0.2 pc) |
| Details | |
| A | |
| Mass | 2.10+0.20 −0.17[7] M☉ |
| Luminosity | 42[8] L☉ |
| Surface gravity (log g) | 3.90±0.14[7] cgs |
| Temperature | 8774+601 −210[1] K |
| Rotational velocity (v sin i) | 191[9] km/s |
| B | |
| Radius | 1.43+0.12 −0.08[3] R☉ |
| Luminosity | 3.966±0.016[3] L☉ |
| Temperature | 6806+203 −258[3] K |
| Age | 635±88[7] Myr |
| Other designations | |
| A: GC 11275, SAO 250164 | |
| B: GC 11276, SAO 250165 | |
| Database references | |
| SIMBAD | data |
The brighter primary, designated component A, has a visual magnitude of 5.27[2] and is an A-type main-sequence star with a stellar classification of A2V.[4] It is 635[7] million years old and is spinning with a projected rotational velocity of 191 km/s.[9] The star has 2.1 times the mass of the Sun.[7]
The magnitude 7.62[2] companion, component B, is a F-type main-sequence star with a class of F2V.[5] It is radiating four[3] times the luminosity of the Sun from its photosphere at an effective temperature of 6,806 K.[3] The system is a source for X-ray emission, which is most likely coming from the secondary.[13]
References
edit- ^ a b c d e f g Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.
- ^ a b c d e f g h i j k Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H
- ^ a b Corbally, C. J. (1984), "Close visual binaries. I. MK classifications", Astrophysical Journal Supplement Series, 55: 657, Bibcode:1984ApJS...55..657C, doi:10.1086/190973.
- ^ a b c d 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.
- ^ a b c d e Gullikson, Kevin; et al. (2016), "The Close Companion Mass-ratio Distribution of Intermediate-mass Stars", The Astronomical Journal, 152 (2): 40, arXiv:1604.06456, Bibcode:2016AJ....152...40G, doi:10.3847/0004-6256/152/2/40, S2CID 119179065.
- ^ McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012), "Fundamental parameters and infrared excesses of Hipparcos stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
- ^ a b Royer, F.; et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics, 393: 897–911, arXiv:astro-ph/0205255, Bibcode:2002A&A...393..897R, doi:10.1051/0004-6361:20020943, S2CID 14070763
- ^ "HD 69863". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-07. Component B.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Letchford, Roderick; et al. (April 2017), "The Southern Double Stars of Carl Rümker I: History, Identification, Accuracy", Journal of Double Star Observations, 13 (2): 220–232, Bibcode:2017JDSO...13..220L.
- ^ Schröder, C.; Schmitt, J. H. M. M. (November 2007), "X-ray emission from A-type stars", Astronomy and Astrophysics, 475 (2): 677−684, Bibcode:2007A&A...475..677S, doi:10.1051/0004-6361:20077429.