Epoch J2000 Equinox J2000
|Right ascension||19h 20m 32.90437s|
|Declination||–05° 24′ 56.7440″|
|Apparent magnitude (V)||5.00|
|Spectral type||G8 III-IV|
|U−B color index||+0.634|
|B−V color index||+0.936|
|R−I color index||0.5|
|Radial velocity (Rv)||–16.91 ± 1.93 km/s|
|Proper motion (μ)||RA: +113.13 mas/yr
Dec.: +46.20  mas/yr
|Parallax (π)||21.15 ± 0.39 mas|
|Distance||154 ± 3 ly
(47.3 ± 0.9 pc)
|Period (P)||266.544 days|
|26 Aquilae A|
|Surface gravity (log g)||3.2 cgs|
|Metallicity [Fe/H]||–0.21 dex|
|Rotational velocity (v sin i)||1.3 km/s|
|26 Aquilae B|
|Mass||1.4 ± 0.05 M☉|
26 Aquilae is the Flamsteed designation for a binary star system in the equatorial constellation of Aquila. It has an apparent visual magnitude of 5.00, which means it is faintly visible to the naked eye. As the Earth orbits the Sun, this star system undergoes a parallax shift of 21.15 mas. This means it is located at a distance of approximately 154 light-years (47 parsecs) from Earth, give or take a 3 light-year margin of error.
This is a single-lined spectroscopic binary system, meaning that the presence of an orbiting companion is revealed through shifts in the spectrum of the primary star. The pair orbit each other with a period of 266.544 days at a high eccentricity of 0.833. Little is known about this companion, although its mass can be estimated as 140% of the mass of the Sun.
The primary component has a stellar classification of G8 III-IV. The luminosity class of III-IV indicates the spectrum resembles that of a star part way between the subgiant and giant stages of its evolution. It has more than three times the mass of the Sun and six times the Sun's radius. It is radiating 21 times as much luminosity as the Sun from this enlarged outer envelope at an effective temperature of 4,940 K. At this heat, the star glows with the characteristic yellow hue of a G-type star.
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