Zeta Aquilae

Zeta Aquilae (ζ Aql, ζ Aquilae) is a double star of stellar classification A0 Vn, with the luminosity class 'V' indicating is a main sequence star that is generating energy through the nuclear fusion of hydrogen at its core. The effective temperature of the star's outer envelope is about 9620 K, which gives it the white hue typical of A-type stars. The estimated age of this star is 50–150 million years.

This star is rotating rapidly, with a projected rotational velocity of 317 km/s⁻¹ giving a lower bound on the azimuthal velocity along the equator. As a result, it has a pronounced equatorial bulge, causing the star to assume an oblate spheroidal shape. The equatorial radius is about 30.7% greater than the polar radius. Because of the Doppler effect, this rapid rotation makes the absorption lines in the star's spectrum broaden and smear out, as indicated by the 'n' suffix in the stellar class.

This star has two faint companions, BD+13 3899B and BD+13 3899C.