Kappa Aquilae
Kappa Aquilae is a star in the equatorial constellation of Aquila. Its name is a Bayer designation that is Latinized from κ Aquilae, and abbreviated Kappa Aql or κ Aql. This is a faint star with an apparent visual magnitude of +4.957, which is bright enough to be seen with the naked eye in dark suburban skies. The annual parallax is only 1.98 mas, which equates to a distance of approximately from Earth.
The spectrum of Kappa Aquilae matches a stellar classification of B0.5 III, where the luminosity class of III is typically associated with evolved giant stars. It is spinning rapidly with a projected rotational velocity of 265 km/s and in the past has been classified as a Be star, despite the lack of an 'e' in the class. However, the weak emission is most likely coming from the outflow of a hot stellar wind rather than a decretion disk. This is a star with 15.50 times the Sun's mass and 12.5 times the radius of the Sun. Massive stars like this are luminous; it is radiating 52,630 times the Sun's luminosity from its outer atmosphere with an effective temperature of 26,500 K, giving it the intense blue-white glow of a B-type star. It is only 11 million years of age.
Etymology
In Chinese, 右旗, meaning Right Flag, refers to an asterism consisting of κ Aquilae, μ Aquilae, σ Aquilae, δ Aquilae, ν Aquilae, 42 Aquilae, ι Aquilae, HD 184701 and 56 Aquilae. Consequently, the Chinese name for κ Aquilae itself is 右旗八This star, together with η Aql, θ Aql, δ Aql, ι Aql and λ Aql were once part of the now-obsolete constellation Antinous.