HD 83446
HD 83446 is a probable astrometric binary[10] star system in the constellation Vela. It is visible to the naked eye with an apparent visual magnitude of 4.34.[2] Based upon an annual parallax shift of 30.5 mas,[1] it is located 107.1 light years from the Sun. The system is moving further away with a heliocentric radial velocity of +18 km/s.[6]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Vela |
| Right ascension | 09h 36m 49.53851s[1] |
| Declination | −49° 21′ 18.0873″[1] |
| Apparent magnitude (V) | 4.34[2] |
| Characteristics | |
| Evolutionary stage | main sequence[3] |
| Spectral type | A7 V[4] |
| B−V color index | 0.173±0.005[2] |
| Variable type | δ Sct[5] |
| Astrometry | |
| Radial velocity (Rv) | +17.8±0.5[6] km/s |
| Proper motion (μ) | RA: −130.55[1] mas/yr Dec.: +42.98[1] mas/yr |
| Parallax (π) | 30.4562 ± 0.1933 mas[1] |
| Distance | 107.1 ± 0.7 ly (32.8 ± 0.2 pc) |
| Absolute magnitude (MV) | 1.79[2] |
| Details | |
| Mass | 1.8+0.11 −0.09[7] M☉ |
| Luminosity | 15.99[2] L☉ |
| Surface gravity (log g) | 4.3±0.14[7] cgs |
| Temperature | 8,331±283[7] K |
| Rotational velocity (v sin i) | 155[8] km/s |
| Age | 453+256 −278[7] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The visible component is an A-type main-sequence star with a stellar classification of A7 V.[4] Observations with the BRITE constellation led to this star's identification as a Delta Scuti variable with pulsation frequencies of 31.0806 and 34.2098 cycles per day, corresponding to periods of 46.3 and 42.1 minutes, respectively.[5] It has a high rate of spin with a projected rotational velocity of 155 km/s, which is giving the star an oblate shape with an equatorial bulge that is 6% larger than the polar radius.[8] The star is roughly 453[7] million years old with 1.8[7] times the mass of the Sun. It is radiating 16[2] times the Sun's luminosity from its photosphere at an effective temperature of 8,331 K.[7]
References edit
- ^ a b c d e f 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 f 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.
- ^ Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
- ^ a b Gray, R. O.; et al. (July 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): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ a b Zwintz, K. (September 2017), "A BRITE view on δ Scuti and γ Doradus stars", in Zwintz, Konnstanze; Poretti, Ennio (eds.), Second BRITE-Constellation Science Conference: Small satellites—big science, Proceedings of the Polish Astronomical Society volume 5, held 22-26 August, 2016 in Innsbruck, Austria, vol. 5, Bartycka 18, 00-716 Warsaw, Poland: Polish Astronomical Society, pp. 228–235, arXiv:1611.04917, Bibcode:2017sbcs.conf..228Z
{{citation}}: CS1 maint: location (link) - ^ a b 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 c d e f g 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.
- ^ a b Belle, G. T. (2012), "Interferometric observations of rapidly rotating stars", The Astronomy and Astrophysics Review, 20 (1): 51, arXiv:1204.2572, Bibcode:2012A&ARv..20...51V, doi:10.1007/s00159-012-0051-2, S2CID 119273474.
- ^ "HD 83446". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-08-08.
- ^ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.