Sirius is the brightest star visible in Earth's night sky. While many believe the sun is the brightest star, Sirius has a visual magnitude of 1.46, making it nearly twice as bright as Canopus, the next brightest star. Sirius is actually a binary star system composed of Sirius A and Sirius B located between 8.2 and 31.5 astronomical units apart. As Sirius moves closer to the solar system over the next 60,000 years, it will increase in brightness before beginning to dim after 210,000 years, but it will remain the brightest star visible from Earth.