56 Aquilae

56 Aquilae
Observation data
Epoch J2000      Equinox J2000
Constellation Aquila
Right ascension 19h 54m 08.27613s
Declination −08° 34 27.1674
Apparent magnitude (V) 5.79
Characteristics
Spectral type K5 III
U−B color index +2.00
B−V color index +1.664±0.006
Astrometry
Radial velocity (Rv)−49.5±2.9 km/s
Proper motion (μ) RA: +6.737 mas/yr
Dec.: −18.578 mas/yr
Parallax (π)5.6650±0.1739 mas
Distance580 ± 20 ly
(177 ± 5 pc)
Absolute magnitude (MV)−0.66
Details
Radius41.7+2.0
−2.6
 R
Luminosity391±14 L
Temperature3,972+130
−91
 K
Other designations
56 Aql, BD−08°5150, FK5 2131, GC 2343, HD 188154, HIP 97928, HR 7584, SAO 143894
Database references
SIMBADdata

56 Aquilae is a single star in the equatorial constellation of Aquila. 56 Aquilae is its Flamsteed designation. Its apparent visual magnitude is 5.79, 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 580 light years away from the Sun, based on parallax. It is moving closer to the Earth with a heliocentric radial velocity of −50 km/s, and is predicted to come as near as 222 light-years in around 3.3 million years.

This is an aging giant star with a stellar classification of K5 III, having exhausted the supply of hydrogen at its core and expanded to 42 times the Sun's radius. It is radiating 391 times the luminosity of the Sun from its photosphere at an effective temperature of 3,972 K. 56 Aquilae is a double star, but it does not appear to be a binary star system. It is one of the double stars profiled in Admiral William Henry Smyth's 1864 work, Sidereal Chromatics.