HD 188753
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cygnus | 
| Right ascension | 19h 54m 58.37177s | 
| Declination | +41° 52′ 17.5298″ | 
| Apparent magnitude (V) | +7.43 | 
| Characteristics | |
| Spectral type | A: G8V Ba: K0V Bb: K7V | 
| U−B color index | +0.42 | 
| B−V color index | +0.79 | 
| Astrometry | |
| Radial velocity (Rv) | −23.5 km/s | 
| Proper motion (μ) | RA: −51.32 mas/yr Dec.: +286.57 mas/yr | 
| Parallax (π) | 21.63±0.65 mas | 
| Distance | 151 ± 5 ly (46 ± 1 pc) | 
| Absolute magnitude (MV) | 4.09 | 
| Orbit | |
| Primary | HD 188753 A | 
| Companion | HD 188753 B | 
| Period (P) | 25.63 yr | 
| Semi-major axis (a) | 0.2587" (11.8 au) | 
| Eccentricity (e) | 0.502 | 
| Inclination (i) | 31.1° | 
| Longitude of the node (Ω) | 45.7° | 
| Periastron epoch (T) | 1988.1 | 
| Argument of periastron (ω) (secondary) | 233.3° | 
| Semi-amplitude (K1) (primary) | 4.8 km/s | 
| Semi-amplitude (K2) (secondary) | 3.4 km/s | 
| Orbit | |
| Primary | Ba | 
| Companion | Bb | 
| Period (P) | 154.448 days | 
| Eccentricity (e) | 0.175 | 
| Inclination (i) | 41±3° | 
| Semi-amplitude (K1) (primary) | 13.479 km/s | 
| Semi-amplitude (K2) (secondary) | 17.63 km/s | 
| Details | |
| Mass | A: 1.06±0.07 M☉ Ba: 0.96±0.05 M☉ Bb: 0.67±0.05 M☉ | 
| Temperature | A: 5,750 K | 
| Other designations | |
| BD+41 3535, HIP 98001, SAO 48968, ADS 13125, WDS J19550+4152 | |
| Database references | |
| SIMBAD | data | 
HD 188753 is a hierarchical triple star system approximately 151 light-years away in the constellation of Cygnus, the Swan. In 2005, an extrasolar planet was announced to be orbiting the primary star (designated HD 188753 A) in the system. Follow-up measurements by an independent group in 2007 did not confirm the planet's existence.