The system is between 200 and 300 million years old. It is 25 times as luminous as the Sun, but has a significantly lower luminosity than other bright stars such as Canopus or Rigel. Sirius A is about twice as massive as the Sun ( M ☉) and has an absolute visual magnitude of +1.42.
After that time, its distance will begin to increase, and it will become fainter, but it will continue to be the brightest star in the Earth's night sky for approximately the next 210,000 years. Sirius is gradually moving closer to the Solar System, so it is expected to slightly increase in brightness over the next 60,000 years. At a distance of 2.64 parsecs (8.6 ly), the Sirius system is one of Earth's nearest neighbours. Sirius appears bright because of its intrinsic luminosity and its proximity to the Solar System. The distance between the two varies between 8.2 and 31.5 astronomical units as they orbit every 50 years. Sirius is a binary star consisting of a main-sequence star of spectral type A0 or A1, termed Sirius A, and a faint white dwarf companion of spectral type DA2, termed Sirius B. With a visual apparent magnitude of −1.46, Sirius is almost twice as bright as Canopus, the next brightest star. The star is designated α Canis Majoris, Latinized to Alpha Canis Majoris, and abbreviated Alpha CMa or α CMa.
Its name is derived from the Greek word Σείριος ( Seirios, lit.
Sirius ( / ˈ s ɪr i ə s/) is the brightest star in the night sky. Dog Star, Aschere, Canicula, Al Shira, Sothis, Alhabor,
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