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
The Sirius Mystery Culture". One unproven aspect of the reported Dogon knowledge of the Sirius system is the assertion that the Dogon knew of another star in the Sirius system, Emme Ya, or "larger than Sirius B but lighter and dim in magnitude." A dynamical study published in 1995, based on anomalous perturbations of Sirius B (suggestive of the star being gravitationally influenced by another body) concluded that the presence of a third star orbiting Sirius could not be ruled out. An apparent "third star" observed in the 1920s is now confirmed as a background object, something previously suggested by Holberg in 2007: