HD 181655
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| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Lyra[1] |
| Right ascension | 19h 19m 38.9987s[2] |
| Declination | +37° 19′ 49.946″[2] |
| Apparent magnitude (V) | +6.29[1] |
| Characteristics | |
| Evolutionary stage | main sequence[3] |
| Spectral type | G5V + G5V[3] |
| B−V color index | 0.676±0.003[1] |
| Astrometry | |
| Radial velocity (Rv) | +1.827±0.031[3] km/s |
| Proper motion (μ) | RA: −61.4 mas/yr[2] Dec.: −183.7 mas/yr[2] |
| Parallax (π) | 41.08±0.77 mas[3] |
| Distance | 79.4 ± 1.5 ly (24.34±0.45 pc)[3] |
| Absolute magnitude (MV) | +4.27[1] |
| Orbit[3] | |
| Period (P) | 331.609±0.0037 days |
| Semi-major axis (a) | (47.432±0.035)×10−3" (1.156 au) |
| Eccentricity (e) | 0.9322±0.00013 |
| Inclination (i) | 29.48±0.86° |
| Longitude of the node (Ω) | 181.046±0.092° |
| Periastron epoch (T) | 58,142.690±0.0027 HJD |
| Argument of periastron (ω) (secondary) | 169.888±0.075° |
| Semi-amplitude (K1) (primary) | 25.555±0.047 km/s |
| Semi-amplitude (K2) (secondary) | 25.947±0.048 km/s |
| Details[3] | |
| A | |
| Mass | 0.941±0.076 M☉ |
| Radius | 0.95 R☉ |
| Rotational velocity (v sin i) | 2.6±1.0 km/s |
| B | |
| Mass | 0.926±0.075 M☉ |
| Radius | 0.95 R☉ |
| Rotational velocity (v sin i) | 2.6±1.0 km/s |
| Other designations | |
| BD+37°3417, GJ 754.2, GJ 9654, HD 181655, HIP 94981, HR 7345, TYC 2665-2093-1[4] | |
| Database references | |
| SIMBAD | data |
HD 181655 (HR 7345) is a binary star in the constellation Lyra. At an apparent magnitude of +6.29, it is very faintly visible to the naked eye in locations far from light pollution. Dynamical parallax measurements give a distance of 79.4 light-years (24.34 parsecs) light-years.