HD 188405
Binary star system in the constellation Aquila
From Wikipedia, the free encyclopedia
HD 188405 is a binary star in the equatorial constellation of Aquila. The pair have an orbital period of roughly 425 years and an angular separation of 1.085″.[8]
Right ascension19h 55m 19.50021s[2]
Declination−06° 44′ 05.2223″[2]
Apparentmagnitude(V)6.51[3] (6.94 + 7.98)[4]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila[1] |
| Right ascension | 19h 55m 19.50021s[2] |
| Declination | −06° 44′ 05.2223″[2] |
| Apparent magnitude (V) | 6.51[3] (6.94 + 7.98)[4] |
| Characteristics | |
| Spectral type | F2V[4] |
| U−B color index | +0.05[3] |
| B−V color index | +0.39[3] |
| Astrometry | |
| Radial velocity (Rv) | −13.10[5] km/s |
| Proper motion (μ) | RA: +16.58[2] mas/yr Dec.: −60.18[2] mas/yr |
| Parallax (π) | 12.22±0.84 mas[2] |
| Distance | 270 ± 20 ly (82 ± 6 pc) |
| Absolute magnitude (MV) | +1.94[1] |
| Orbit[6] | |
| Period (P) | 425±22 yr |
| Semi-major axis (a) | 1.085±0.024″ |
| Eccentricity (e) | 0.9414±0.0020 |
| Inclination (i) | 103.05±0.84° |
| Longitude of the node (Ω) | 264.03±0.77° |
| Periastron epoch (T) | B 1974.28±0.23 |
| Argument of periastron (ω) (secondary) | 327.9±1.7° |
| Details | |
| HD 188405 A | |
| Mass | 1.4[7] M☉ |
| Radius | 2.8[7] R☉ |
| Luminosity | 13[7] L☉ |
| Temperature | 6,646[7] K |
| Other designations | |
| BD−07°5102, HD 188405, HIP 98038, HR 7599, SAO 143911 | |
| Database references | |
| SIMBAD | data |
