56 Aquilae
K-type giant star in the constellation Aquila
From Wikipedia, the free encyclopedia
56 Aquilae is a single[10] star in the equatorial constellation of Aquila. 56 Aquilae is its Flamsteed designation. Its apparent visual magnitude is 5.79,[2] meaning it is barely visible to the naked eye as a dim, orange-hued point of light, under ideal viewing conditions. The star is located at a distance of around 593 light years away from the Sun, based on parallax.[1] It is moving closer to the Earth with a heliocentric radial velocity of −50 km/s,[5] and is predicted to come as near as 222 light-years in around 3.3 million years.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila |
| Right ascension | 19h 54m 08.27657s[1] |
| Declination | −08° 34′ 27.1592″[1] |
| Apparent magnitude (V) | 5.79[2] |
| Characteristics | |
| Evolutionary stage | red giant branch[1] |
| Spectral type | K5 III[3] |
| U−B color index | +2.00[2] |
| B−V color index | +1.664±0.006[4] |
| Astrometry | |
| Radial velocity (Rv) | −49.5±2.9[5] km/s |
| Proper motion (μ) | RA: +6.321[1] mas/yr Dec.: −19.121[1] mas/yr |
| Parallax (π) | 5.5025±0.0807 mas[1] |
| Distance | 593 ± 9 ly (182 ± 3 pc) |
| Absolute magnitude (MV) | −0.66[4] |
| Details | |
| Mass | 1.23[6] M☉ |
| Radius | 43[7] R☉ |
| Luminosity | 896[1] L☉ |
| Surface gravity (log g) | 1.02[8] cgs |
| Temperature | 3,885[8] K |
| Metallicity [Fe/H] | −0.26[6] dex |
| Age | 13.4[8] Gyr |
| Other designations | |
| 56 Aql, BD−08°5150, FK5 2131, GC 2343, HD 188154, HIP 97928, HR 7584, SAO 143894[9] | |
| Database references | |
| SIMBAD | data |
This is an aging giant star with a stellar classification of K5 III,[3] having exhausted the supply of hydrogen at its core and expanded to 43 times the Sun's radius.[7] It is radiating 896 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 3,885 K.[8] 56 Aquilae is a double star,[11] but it does not appear to be a binary star system.[10] It is one of the double stars profiled in Admiral William Henry Smyth's 1864 work, Sidereal Chromatics.