Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Kappa Herculis is a double star in the constellation Hercules. Kappa Herculis is a giant star with stellar classification G8III. With a mass of 3.0 Mo and radius that is 16 Ro, the star boasts a total bolometric luminosity that is 150 Lo. Its apparent magnitude has been recently recalibrated at 5.1628. The Hipparcos mission estimated its distance at roughly 120 parsecs from Earth, or 390 ± 20 light years away.