Sirius its constellation, Canis Major (Greater Dog). The heliacal rising of Sirius marked the flooding of the Nile in Ancient Egypt and the "dog days" of summer for the ancient Greeks, while to the Polynesians in the Southern Hemisphere the star marked winter and was an important reference for their navigation around the Pacific Ocean. The brightest star in the night sky, Sirius is recorded in the earliest astronomical records. Its displacement from the ecliptic causes this heliacal rising to be remarkably regular compared to other stars, with a period of almost exactly 365.25 days holding it constant relative to the
Sirius Sirius Sirius (, a latinisation of Greek , "Seirios", ."glowing" or "scorching") is a binary star and the brightest point of light in the night sky. With a visual apparent magnitude of −1.46, it is almost twice as bright as Canopus, the next brightest star. The system has the Bayer designation α (Alpha) Canis Majoris. The binary system consists of a main-sequence star of spectral type A0 or A1, termed Sirius A, and a faint white dwarf companion of spectral type DA2, designated Sirius B. The distance between the two varies between 8.2 and 31.5 astronomical units as they orbit