So it will be visible from the southern hemisphere only.Īfter 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, at which point Vega, another A-type star that is intrinsically more luminous than Sirius, becomes the brightest star. This is due to precession and proper motion of Sirius itself which moves slowly in the SSW direction. In that year, Sirius will come to within 1.6 degrees of the south celestial pole. Sirius is gradually moving closer to the Solar System it is expected to increase in brightness slightly over the next 60,000 years to reach a peak magnitude of −1.68.Ĭoincidentally, at about the same time, Sirius will take its turn as the southern Pole Star, around the year 66270. 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 α CMa or Alpha CMa. Its name is derived from the Greek word Σείριος, or Seirios, meaning lit. Sirius is the brightest star in the night sky. Dog Star, Aschere, Canicula, Al Shira, Sothis, Alhabor,
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