2 Persei
2 Persei is a binary star system in the northern constellation Perseus, located around 500 light years away from the Sun. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude is 5.70.[2] The system is moving further away from the Earth with a heliocentric radial velocity of 11 km/s.[4]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 01h 52m 09.37243s[1] |
| Declination | +50° 47′ 34.0662″[1] |
| Apparent magnitude (V) | 5.70[2] |
| Characteristics | |
| Spectral type | B9pHgMn[3] |
| B−V color index | −0.067±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | 11.4±0.2[4] km/s |
| Proper motion (μ) | RA: +17.454[1] mas/yr Dec.: −29.871[1] mas/yr |
| Parallax (π) | 6.5107 ± 0.1939[1] mas |
| Distance | 500 ± 10 ly (154 ± 5 pc) |
| Absolute magnitude (MV) | −0.14[2] |
| Orbit[4] | |
| Primary | 2 Persei A |
| Companion | 2 Persei B |
| Period (P) | 5.62698±0.00002 d |
| Eccentricity (e) | 0.024±0.011 |
| Periastron epoch (T) | 2440281.3±0.4 JD |
| Argument of periastron (ω) (primary) | 208±24° |
| Semi-amplitude (K1) (primary) | 26.5±0.3 km/s |
| Details | |
| Luminosity | 145.30[2] L☉ |
| Temperature | 9,412[1] K |
| Rotational velocity (v sin i) | 25[5] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
In 1970 radial velocity measurements from spectrograms taken at David Dunlap Observatory indicated it was a single-lined spectroscopic binary.[7][5] Follow up observations led to the determination that it had a nearly circular orbit with a period of 5.6 days.[4] The visible component is a chemically peculiar mercury-manganese star with a stellar classification of B9pHgMn.[3] Other analyses of its spectrum have assigned it the giant star spectral type of B9III.[8]
References
- 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.
- Cowley, A.; et al. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal. 74: 375–406. Bibcode:1969AJ.....74..375C. doi:10.1086/110819.
- Heard, J. F.; Krautter, A. (1975). "The orbit of the spectroscopic binary HD 11291". Journal of the Royal Astronomical Society of Canada. 69: 22–24. Bibcode:1975JRASC..69...22H.
- Abt, Helmut A.; et al. (July 2002). "Rotational Velocities of B Stars". The Astrophysical Journal. 573 (1): 359–365. Bibcode:2002ApJ...573..359A. doi:10.1086/340590.
- "2 Per". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-03-19.
- Hube, Douglas P. (1970). "The radial velocities of 335 late B-type stars". Memoirs of the Royal Astronomical Society. 72: 233–280. Bibcode:1970MmRAS..72..233H.
- Sato, K.; Kuji, S. (November 1990). "MK classification and photometry of stars used for time and latitude observations at Mizusawa and Washington". Astronomy and Astrophysics Supplement Series. 85 (3): 1069–1087. Bibcode:1990A&AS...85.1069S.