Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Lambda Sagittarii is a star within the constellation Sagittarius. The star marks the top of the Archer's bow, whence its traditional name Kaus Borealis. It also marks the top of the lid of the so-called "Teapot" asterism. In ancient Chinese astronomy, it is the 2nd of 6 stars in the Dipper or 'South Dipper' mansion of the Black Tortoise of the North. Kaus Borealis is a spectral class K orange giant star. It is currently fusing helium into carbon and oxygen in its core. Kaus Borealis is 77 light years from us, with a mass 2.3 times that of the Sun. It is 52 times more luminous than the Sun and has a radius of some 11 Suns.