Sirius, also known as the Dog Star, is the brightest star in the night sky. It is located in the constellation Canis Major and is about 8.6 light-years away from Earth. Sirius is actually a binary star system, consisting of two stars: Sirius A, a main-sequence star, and Sirius B, a white dwarf. Sirius has been significant in various cultures throughout history. For example, in ancient Egypt, its rising marked the start of the Nile flooding season, which was crucial for agriculture. The star's brightness and prominence have made it a key reference point for navigation and timekeeping.