brightest star in the sky | |
Sirius is actually a system of two stars in orbit around each other. Almost all the light comes from the primary star, Sirius A, which is a normal star about 2.3 times more massive than the Sun and white in colour. Its faint companion, Sirius B, was discovered visually in 1862, and is a white dwarf star. It gives out only one ten- thousandth the light of Sirius A. The pair take 50 years to complete one orbit. |