Sirius astrological symbol was listed by Heinrich Cornelius Agrippa. Many cultures have historically attached special significance to Sirius, particularly in relation to dogs. It is often colloquially called the "Dog Star" as the brightest star of Canis Major, the "Great Dog" constellation. It was classically depicted as Orion's dog. The Ancient Greeks thought that Sirius's emanations could affect dogs adversely, making them behave abnormally during the "dog days," the hottest days of the summer. The Romans knew these days as "dies caniculares", and the star Sirius was called Canicula, "little dog." The excessive panting of dogs in hot weather was thought
Sirius approximately 296,000 years. Sirius is a binary star system consisting of two white stars orbiting each other with a separation of about 20 AU (roughly the distance between the Sun and Uranus) and a period of 50.1 years. The brighter component, termed Sirius A, is a main-sequence star of spectral type early A, with an estimated surface temperature of 9,940 K. Its companion, Sirius B, is a star that has already evolved off the main sequence and become a white dwarf. Currently 10,000 times less luminous in the visual spectrum, Sirius B was once the more massive of the two.