Iota Cassiopeiae
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cassiopeia |
| ι Cas A | |
| Right ascension | 02h 29m 03.960s |
| Declination | +67° 24′ 08.70″ |
| Apparent magnitude (V) | 4.61 (4.65 / 8.48) |
| ι Cas B | |
| Right ascension | 02h 29m 03.567s |
| Declination | +67° 24′ 07.01″ |
| Apparent magnitude (V) | 6.87 |
| ι Cas C | |
| Right ascension | 02h 29m 05.086s |
| Declination | +67° 24′ 05.53″ |
| Apparent magnitude (V) | 9.05 (9.14 / 11.84) |
| Characteristics | |
| U−B color index | +0.03 |
| B−V color index | +0.12 |
| ι Cas A | |
| Spectral type | A3p / G6 |
| Variable type | α2 CVn |
| ι Cas B | |
| Spectral type | F5 |
| ι Cas C | |
| Spectral type | K4 / M2 |
| U−B color index | +0.18 |
| B−V color index | +0.72 |
| Astrometry | |
| Radial velocity (Rv) | 1.2±2 km/s |
| Proper motion (μ) | RA: −26.61 mas/yr Dec.: 38.21 mas/yr |
| Parallax (π) | 22.22±0.08 mas |
| Distance | 146.8 ± 0.5 ly (45.0 ± 0.2 pc) |
| Absolute magnitude (MV) | 1.62±0.07 (Aa) 5.60±0.17 (Ab) |
| Orbit | |
| Primary | ι Cas Aa |
| Name | ι Cas Ab |
| Period (P) | 48.72±0.45 yr |
| Semi-major axis (a) | 0.423±0.004″ |
| Eccentricity (e) | 0.637±0.004 |
| Inclination (i) | 148.2±1.3° |
| Longitude of the node (Ω) | 176.6±1.8° |
| Periastron epoch (T) | B 1993.21±0.05 |
| Argument of periastron (ω) (secondary) | 328.2±1.9° |
| Orbit | |
| Primary | ι Cas A |
| Name | ι Cas B |
| Period (P) | 2,400 yr |
| Semi-major axis (a) | 6.50″ |
| Eccentricity (e) | 0.40 |
| Inclination (i) | 102.9±0.3° |
| Longitude of the node (Ω) | 188.0±0.9° |
| Periastron epoch (T) | B 940±47 |
| Argument of periastron (ω) (secondary) | 113.3±3.4° |
| Details | |
| ι Cas Aa | |
| Mass | 1.98 M☉ |
| Radius | 2.3±0.4 R☉ |
| Luminosity | 24 L☉ |
| Temperature | 8,360±275 K |
| Rotation | 1.74033 d |
| Rotational velocity (v sin i) | 48 km/s |
| Age | 100 Myr |
| ι Cas Ab | |
| Mass | 0.98 M☉ |
| ι Cas B | |
| Mass | 1.28 M☉ |
| Temperature | 6,540 K |
| ι Cas Ca | |
| Temperature | 4,520±20 K |
| ι Cas Cb | |
| Temperature | 3,590±45 K |
| Other designations | |
| Huagai, BD+66°213, HD 15089, HIP 11569, HR 707, SAO 12298 | |
| ι Cas A: TYC 4058-1504-1 | |
| ι Cas B: TYC 4058-1504-2 | |
| ι Cas C: TYC 4058-1505-1 | |
| Database references | |
| SIMBAD | ι Cas |
| ι Cas A | |
| ι Cas B | |
| ι Cas C | |
Iota Cassiopeiae, also named Huagai, is a multiple star system in the constellation Cassiopeia. Its name is a Bayer designation that is Latinized from ι Cassiopeiae, and abbreviated Iota Cas or ι Cas. The system has a combined apparent magnitude of about 4.5, making it visible to the naked eye. Based on its parallax, it is located about 133 light-years (41 pc) 133 light-years (41 parsecs) from Earth.