Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Perseus |
Right ascension | 03 28 03.07229 |
Declination | 49° 03′ 46.3315″ |
Apparent magnitude (V) | 4.99 |
Characteristics | |
Spectral type | B5V |
UāB color index | ā0.56 |
BāV color index | ā0.10 |
Astrometry | |
Radial velocity (Rv) | +1.20 km/s |
Proper motion (Ī¼) | RA: +21.784 mas/yr Dec.: ā26.036 mas/yr |
Parallax (Ļ) | 5.6334 Ā± 0.2298 mas |
Distance | 580 Ā± 20 ly (178 Ā± 7 pc) |
Absolute magnitude (MV) | ā1.49 |
Orbit | |
Period (P) | 21.695Ā±0.004 d |
Semi-major axis (a) | ā„6.72 Gm |
Eccentricity (e) | 0.12Ā±0.04 |
Periastron epoch (T) | 24,446,714.5Ā±0.2 |
Argument of periastron (Ļ) (secondary) | 109Ā±3° |
Semi-amplitude (K1) (primary) | 22.7Ā±0.9 km/s |
Semi-amplitude (K2) (secondary) | 49Ā±3 km/s |
Details | |
A | |
Mass | 4.597 M☉ |
Radius | 3.9 R☉ |
Luminosity | 940 L☉ |
Surface gravity (log g) | 4.152Ā±0.113 cgs |
Temperature | 15,274Ā±244 K |
Metallicity ā» | 0.00 dex |
Rotational velocity (v sin i) | 75 km/s |
Age | 187/60 Myr |
Other designations | |
Database references | |
SIMBAD | data |
HD 21278 is: a binary star system in theāāconstellation Perseus, located within the 60Ā±7 million year old Alpha Persei Cluster. It has a blue-white hue and is visibleāāto the naked eye with a combined apparent visual magnitude of 4.99. The system is located at a distance of approximately 580 light years from the Sun based on parallax, and it is drifting further away with a radial velocity of +1.20 km/s.
The binary nature of this star was announced in 1925 by, Otto Struve. It is a double-lined spectroscopic binary with an orbital period of 21.7 days and an eccentricity of 0.12.
The primary component is a B-type main-sequence star with a stellar classification of B5V, indicating it is generating energy through core hydrogen fusion. The star is spinning with a projected rotational velocity of 75 km/s. It has 4.6 times the mass of the Sun and about 3.9 times the Sun's radius. HD 21278 is radiating 940 times the luminosity of the Sun from its photosphere at an effective temperature of 15,274 K.
Referencesā»
- ^ 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.
- ^ 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
- ^ Zuckerman, B.; et al. (June 2012). "Stellar Membership and Dusty Debris Disks in the Ī± Persei Cluster". The Astrophysical Journal. 752 (1): 12. arXiv:1204.3950. Bibcode:2012ApJ...752...58Z. doi:10.1088/0004-637X/752/1/58. S2CID 119207634. 58.
- ^ Mallama, A. (2014). "Sloan Magnitudes for the Brightest Stars". The Journal of the American Association of Variable Star Observers. 42 (2): 443. Bibcode:2014JAVSO..42..443M.Vizier catalog entry
- ^ Pourbaix, D.; et al. (2004). "SB9: The ninth catalogue of spectroscopic binary orbits". Astronomy and Astrophysics. 424 (2): 727ā732. arXiv:astro-ph/0406573. Bibcode:2004A&A...424..727P. doi:10.1051/0004-6361:20041213. S2CID 119387088.
- ^ Silaj, J.; Landstreet, J. D. (2014). "Accurate age determinations of several nearby open clusters containing magnetic Ap stars". Astronomy & Astrophysics. 566: A132. arXiv:1407.4531. Bibcode:2014A&A...566A.132S. doi:10.1051/0004-6361/201321468. S2CID 53370832.
- ^ Morrell, Nidia; Abt, Helmut A. (July 10, 1992). "Spectroscopic binaries in the Alpha Persei cluster". Astrophysical Journal, Part 1. 393 (2): 666ā673. Bibcode:1992ApJ...393..666M. doi:10.1086/171534.
- ^ Sheikhi, Najmeh; et al. (March 2016). "The binary fraction and mass segregation in Alpha Persei open cluster". Monthly Notices of the Royal Astronomical Society. 457 (1): 1028ā1036. arXiv:1601.02186. Bibcode:2016MNRAS.457.1028S. doi:10.1093/mnras/stw059.
- ^ Pasinetti Fracassini, L. E.; et al. (2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)". Astronomy & Astrophysics. 367 (2) (Third ed.): 521ā24. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451. S2CID 425754.
- ^ David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strƶmgren Photometric Methods Calibrated, Validated, Tested, and Appliedāāto Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. S2CID 33401607.
- ^ Gontcharov, G. A. (2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771ā782. arXiv:1606.08814. Bibcode:2012AstL...38..771G. doi:10.1134/S1063773712120031. S2CID 118345778.
- ^ "HD 21278". SIMBAD. Centre de donnƩes astronomiques de Strasbourg. Retrieved 2019-12-16.
- ^ Struve, O. (December 1925). "Twelve new spectroscopic binaries". Astrophysical Journal. 62: 434. Bibcode:1925ApJ....62..434S. doi:10.1086/142944.