Mu Aquilae

Mu Aquilae
Location of μ Aquilae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aquila
Right ascension 19h 34m 05.353s
Declination +07° 22 44.18
Apparent magnitude (V) 4.45
Characteristics
Evolutionary stage red clump
Spectral type K3-IIIb Fe0.5
U−B color index +1.24
B−V color index +1.176
R−I color index 0.61
Astrometry
Radial velocity (Rv)−24.73±0.13 km/s
Proper motion (μ) RA: +213.280 mas/yr
Dec.: −156.953 mas/yr
Parallax (π)29.4091±0.1441 mas
Distance110.9 ± 0.5 ly
(34.0 ± 0.2 pc)
Absolute magnitude (MV)1.80
Details
Mass1.16±0.10 M
Radius7.43±0.15 R
Luminosity24.5 L
Surface gravity (log g)2.70±0.06 cgs
Temperature4,567±79 K
Metallicity [Fe/H]0.16 dex
Rotational velocity (v sin i)0.0 km/s
Age6.71±2.19 Gyr
Other designations
μ Aql, 38 Aql, BD+07 4132, FK5 1511, GJ 9661, HD 184406, HIP 96229, HR 7429, SAO 124799, LTT 15709
Database references
SIMBADdata

Mu Aquilae is a single star in the equatorial constellation of Aquila. Its name is a Bayer designation that is Latinized from μ Aquilae, and abbreviated Mu Aql or μ Aql. With an apparent visual magnitude of 4.45, it is visible to the naked eye. The measured annual parallax shift of this star is 29.4 mas, which gives a distance estimate of 110.9 light-years (34.0 parsecs) from Earth. It is drifting closer with a radial velocity of −25 km/s, and displays a relatively high proper motion, traversing the celestial sphere at the rate of 0.264 per year.

The stellar classification of Mu Aquilae is K3-IIIb Fe0.5, indicating that this is an evolved giant star with a mild overabundance of iron appearing in its spectrum. It belongs to a sub-category of giants called the red clump, which means it is generating energy through the fusion of helium at its core. Compared to the Sun, it has 116% of the mass and has expanded to 7.7 times the size. This inflated outer envelope has an effective temperature of 4,567 K and is radiating 24.5 times the Sun's luminosity. At this heat, Mu Aquilae glows with the orange hue of a K-type star. It is roughly seven billion years old.