| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 01h 52m 09.3723s[1] |
| Declination | +50° 47′ 34.054″[1] |
| Apparent magnitude (V) | 5.70[2] |
| Characteristics | |
| Spectral type | B9pHgMn[3] |
| B−Vcolor index | −0.067±0.004[2] |
| Astrometry | |
| Radial velocity (Rv) | 11.4±0.2[4] km/s |
| Proper motion (μ) | RA: +17.532[1]mas/yr Dec.: −29.090[1]mas/yr |
| Parallax (π) | 6.8219±0.1092 mas[1] |
| Distance | 478 ± 8 ly (147 ± 2 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 |
| Periastronepoch (T) | 2440281.3±0.4 JD |
| Argument of periastron (ω) (primary) | 208±24° |
| Semi-amplitude (K1) (primary) | 26.5±0.3 km/s |
| Details | |
| Mass | 3.2[1] M☉ |
| Radius | 3.7[1] R☉ |
| Luminosity | 156[1] L☉ |
| Surface gravity (log g) | 3.74[1] cgs |
| Temperature | 11,218[1] K |
| Metallicity [Fe/H] | −0.74[1] dex |
| Rotational velocity (v sin i) | 25[5] km/s |
| Age | 233[1] Myr |
| Other designations | |
| BD+50°379,FK5 1052,HD 11291,HIP 8714,HR 536,SAO 22696[6] | |
| Database references | |
| SIMBAD | data |
2 Persei is abinary star system in the northernconstellationPerseus, located around 500 light years away from the Sun. It is visible to the naked eye as a faint, blue-white hued star with anapparent visual magnitude is 5.70.[2] The system is moving further away from the Earth with a heliocentricradial velocity of 11 km/s.[4]
In 1970radial velocity measurements fromspectrograms taken atDavid Dunlap Observatory indicated it was a single-linedspectroscopic 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 achemically peculiarmercury-manganese star with astellar classification of B9pHgMn.[3] Other analyses of its spectrum have assigned it thegiant star spectral type of B9III.[8]
