45 Aquilae
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila |
| Right ascension | 19h 40m 43.31912s |
| Declination | −00° 37′ 16.3868″ |
| Apparent magnitude (V) | 5.656 (5.9 + 7.6) |
| Characteristics | |
| Spectral type | A3 IV |
| U−B color index | +0.09 |
| B−V color index | +0.11 |
| Astrometry | |
| Radial velocity (Rv) | −46 km/s |
| Proper motion (μ) | RA: +15.683 mas/yr Dec.: +5.323 mas/yr |
| Parallax (π) | 9.3151±0.1561 mas |
| Distance | 350 ± 6 ly (107 ± 2 pc) |
| Absolute magnitude (MV) | 0.49 |
| Orbit | |
| Primary | 5 Aql Aa |
| Companion | 5 Aql Ab |
| Period (P) | 20.31±0.17 yr |
| Semi-major axis (a) | 0.0850±0.0020″ |
| Eccentricity (e) | 0.054±0.047 |
| Inclination (i) | 158.3±7.9° |
| Longitude of the node (Ω) | 202.0±15.0° |
| Periastron epoch (T) | 1996.06±0.92 |
| Argument of periastron (ω) (secondary) | 346.0±25.0° |
| Details | |
| 45 Aql Aa | |
| Mass | 2.63±0.10 M☉ |
| Luminosity | 75.8+13.8 −11.7 L☉ |
| Temperature | 9,016+167 −165 K |
| Rotational velocity (v sin i) | 75 km/s |
| Other designations | |
| 45 Aql, BD−00°3813, FK5 3573, HD 185762, HIP 96807, HR 7480, SAO 14367, WDS J19407-0037 | |
| Database references | |
| SIMBAD | data |
45 Aquilae, abbreviated 45 Aql, is a triple star system in the equatorial constellation of Aquila. 45 Aquilae is its Flamsteed designation. It is located 350 light-years (110 parsecs) away from Earth, give or take a 6 light-year margin of error, and has a combined apparent visual magnitude of 5.7. The system is moving closer to the Earth with a heliocentric radial velocity of -46 km/s.
Based upon a stellar classification of A3 IV, the primary component of this system is a subgiant star that is in the process of evolving away from the main sequence. The star has 2.6 times the mass of the Sun and is spinning with a projected rotational velocity of 75 km/s. It has an orbiting companion with a period of 20.31 years and an eccentricity of 0.054. At an angular separation of 42.2 arcseconds from this pair is a 12.7 magnitude tertiary companion.