Sirius is the brightest star in the night sky. It is almost twice as bright as Canopus, The next brightest star.The name "Sirius" is derived from Ancient Greek. What we see with our naked eye as a single star is actually a binary star system consisting of two stars, Sirius A which is a white main-sequence star of spectral type A1V and a faint white dwarf companion of spectral type DA2 called Sirius B. The distance between Sirius A and Sirius B is about 8.1 and 31.5 Astronomical Units.Sirius, is known as "Dog Star" which reflects its prominence in its constellation Cains Major.Sirius is at a distance of 2.6 Parsecs ( 8.6 Light Years ) as determined by the Hipparchus Astrometry satellite. It's one of the Earth's near neighbours. Sirius is gradually moving closer to the Solar System so it will slightly increase in brightness over the next 60,000 years. Then, It's distance will recede but it will continue to be the brightest star in the Earth's sky for the next 210,000 years.Sirius A is about twice the size of of our Sun and about 25 times brighter. The age of the system is around 200 to 300 million years. The system was originally of two bright bluish stars.Sirius B turned into a red gaint and is turned into its current state as a white dwarf around 120 million years ago.
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