Psi Aquilae
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila |
| Right ascension | 19h 44m 34.19086s |
| Declination | +13° 18′ 10.0063″ |
| Apparent magnitude (V) | 6.25 |
| Characteristics | |
| Spectral type | B9 III-IV |
| U−B color index | −0.22 |
| B−V color index | −0.04 |
| Astrometry | |
| Radial velocity (Rv) | −19.7±2.5 km/s |
| Proper motion (μ) | RA: +0.561 mas/yr Dec.: −9.950 mas/yr |
| Parallax (π) | 2.8253±0.0752 mas |
| Distance | 1,150 ± 30 ly (354 ± 9 pc) |
| Absolute magnitude (MV) | −1.17 |
| Details | |
| Mass | 3.8 M☉ |
| Radius | 6.5 R☉ |
| Luminosity | 506 L☉ |
| Surface gravity (log g) | 3.41 cgs |
| Temperature | 10,167 K |
| Metallicity [Fe/H] | 0.21 dex |
| Rotation | 7.1 days |
| Rotational velocity (v sin i) | 20 km/s |
| Age | ~247 Myr |
| Other designations | |
| ψ Aql, 48 Aquilae, BD+12°4059, GC 27321, HD 186547, HIP 97139, HR 7511, SAO 105199, PPM 136885 | |
| Database references | |
| SIMBAD | data |
Psi Aquilae is a star in the equatorial constellation of Aquila. Its name is a Bayer designation that is Latinized from ψ Aquilae, and abbreviated Psi Aql or ψ Aql. This is a faint star with an apparent visual magnitude of 6.25, which, according to the Bortle Dark-Sky Scale, can be seen with the naked eye in dark rural skies. The orbit of the Earth causes an annual parallax shift of 2.83 mas, which indicates a distance of approximately 1,150 light-years (350 parsecs). It is drifting closer to the Sun with a radial velocity of −20 km/s.
The spectrum of Psi Aquilae matches a stellar classification of B9 III-IV, with the luminosity class of III-IV indicating the spectrum lies part way between that of a subgiant and a giant star. The effective temperature of the star's outer atmosphere is 10,167 K, giving it the blue-white hue of a B-type star. It has nearly four times the mass of the Sun, 6.5 times its radius, and has a projected rotational velocity of 20 km/s.