Sirius

Sirius, also known as the Dog Star, was a duo of stars in the Sirius system located in the Mutter's Spiral galaxy. (TV: The Curse of the Black Spot)

The twin planets of Androzani Major and Androzani Minor were located in this system. (TV: The Caves of Androzani)

Astronomical data
Sirius was roughly 8.6 light years away from Sol. (AUDIO: Max Warp)

History
Sirius was used as a guide-point for navigation on Earth for much of its early history. It was only later found to consist of two stars. In the 17th century, Sirius was still used for navigation in sailing. When Captain Henry Avery obtained a spaceship, one of his trips was to see Sirius. (TV: The Curse of the Black Spot)