HD 217382 is a suspected binary star[8] system in the northern circumpolar constellation of Cepheus. It is faintly visible to the naked eye with an apparent visual magnitude of 4.70.[2] The distance to HD 217382 is around 373 light years, as determined from an annual parallax shift of 8.74 mas. The system is moving further away with a heliocentric radial velocity of +2.6 km/s.[1] It is a candidate member of the Hyades supercluster and has a peculiar velocity of 9.2 km/s.[9]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Cepheus |
Right ascension | 22h 47m 24.97075s[1] |
Declination | +84° 20′ 46.2312″[1] |
Apparent magnitude (V) | 4.70[2] |
Characteristics | |
Spectral type | K4 III[3] |
B−V color index | 1.418±0.001[2] |
Astrometry | |
Radial velocity (Rv) | +2.57±0.13[1] km/s |
Proper motion (μ) | RA: +98.346[1] mas/yr Dec.: +24.049[1] mas/yr |
Parallax (π) | 8.7418 ± 0.0818 mas[1] |
Distance | 373 ± 3 ly (114 ± 1 pc) |
Absolute magnitude (MV) | −0.49[2] |
Details | |
Radius | 37[4] R☉ |
Luminosity | 317.99[2] L☉ |
Surface gravity (log g) | 1.96±0.18[5] cgs |
Temperature | 4,105±42[5] K |
Metallicity [Fe/H] | +0.09±0.06[5] dex |
Rotational velocity (v sin i) | 1.0[6] km/s |
Other designations | |
Database references | |
SIMBAD | data |
The visible component of this system is an evolved K-type giant star with a stellar classification of K4 III.[3] It is a periodic variable with a frequency of a cycle every 10.64724 days and an amplitude of 0.0041 in magnitude.[3] The star has an estimated 37[4] times the radius of the Sun and is radiating 318[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of about 4,105 K.[5]