HD 89571
Binary star in the constellation Camelopardalis
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HD 89571 (HR 4062) is a binary star[12] located in the northern circumpolar constellation Camelopardalis. It is faintly visible to the naked eye with a combined apparent magnitude of 5.51[3] and is estimated to be 142 light years[2] away from the Solar System. However, it is receding with a heliocentric radial velocity of 3.5 km/s.[5]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Camelopardalis[1] |
| Right ascension | 10h 29m 41.6297s[2] |
| Declination | +84° 15′ 06.949″[2] |
| Apparent magnitude (V) | 5.51±0.01[3] |
| Characteristics | |
| Spectral type | A9 V[4] |
| U−B color index | +0.06[3] |
| B−V color index | +0.23[3] |
| Astrometry | |
| Radial velocity (Rv) | 3.5±2[5] km/s |
| Proper motion (μ) | RA: −145.145 mas/yr[2] Dec.: −21.494 mas/yr[2] |
| Parallax (π) | 23.0490±0.3729 mas[2] |
| Distance | 142 ± 2 ly (43.4 ± 0.7 pc) |
| Absolute magnitude (MV) | +2.48[1] |
| Orbit[6] | |
| Primary | A |
| Name | B |
| Period (P) | 2.20±0.03 yr |
| Semi-major axis (a) | 0.0142±0.0006″ |
| Eccentricity (e) | 0.26±0.11 |
| Details | |
| A | |
| Mass | 1.69[7] M☉ |
| Radius | 1.79[2] R☉ |
| Luminosity | 8.4[8] L☉ |
| Surface gravity (log g) | 4.27[9] cgs |
| Temperature | 7,535[10] K |
| Metallicity [Fe/H] | +0.04[11] dex |
| Rotational velocity (v sin i) | 134±7[10] km/s |
| Age | 710[7] Myr |
| B | |
| Mass | 0.38[7] M☉ |
| Other designations | |
| AG+84°229, BD+84°234, GC 14305, HD 89571, HIP 51384, HR 4062, SAO 1701, WDS J10297+8415AB | |
| Database references | |
| SIMBAD | data |
The primary has a stellar classification of A9 V,[4] indicating that it is an ordinary A-type main-sequence star. David S. Evans gave it a slightly warmer class of A6 V[13] while Cowley et al. classified it as F0 IV,[14] indicating a F-type subgiant. Nevertheless, the two components take roughly 2 years to orbit each other at a mean separation of 14.2 mas.[6]
The components have masses of 1.69 M☉ and 0.38 M☉,[7] with the latter being a probable M-type star. HD 89571 has a radius of 1.79 R☉[2] and a luminosity of 8.4 L☉.[8] This yields an effective temperature of 7,535 K,[10] giving a white hue. It is estimated to be 710 million years old[7] and spins rapidly with a projected rotational velocity of 134 km/s;[10] it has a near solar metallicity, equating to an iron abundance 110% that of the Sun.[11]