Sirius
binary star system in the constellation of Canis Major
Sirius is the brightest star in the night sky, located in the southern constellation of Canis Major. Its name is derived from the Ancient Greek word Σείριος (Latin script: Seirios; lit. 'glowing' or 'scorching'). The star is designated α Canis Majoris, Romanized to Alpha Canis Majoris, and abbreviated α CMa or Alpha CMa. With a visual apparent magnitude of −1.46, Sirius is almost twice as bright as Canopus, the next brightest star. 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. The distance between the two varies between 8.2 and 31.5 astronomical units as they orbit every 50 years.
Sirius appears bright because of its intrinsic luminosity and its proximity to the Solar System. At a distance of 2.64 parsecs (8.6 ly), the Sirius system is one of Earth's nearest neighbours. Sirius is gradually moving closer to the Solar System and it is expected to increase in brightness slightly over the next 60,000 years to reach a peak magnitude of −1.68.
Coincidentally, at about the same time, Sirius will take its turn as the southern Pole Star, around the year 66,270 AD. In that year, Sirius will come to within 1.6 degrees of the south celestial pole. This is due to axial precession and proper motion of Sirius itself which moves slowly in the SSW direction, so it will be visible from the southern hemisphere only.
The public source identifies “Sirius” as binary star system in the constellation of Canis Major. This brief keeps that definition visible, then builds a research path around Sirius, binary and star.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Sirius”, the useful work is to connect “binary star system in the constellation of Canis Major” to the records capable of establishing context and consequence.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 25, 2026. The linked authority identifier is Q3409. VIAF identifies the subject as 316429980. The Library of Congress control number is sh85122983. 1 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “Sirius” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.