31 Facts About Sirius


Sirius appears bright because of its intrinsic luminosity and its proximity to the Solar System.

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Sirius is gradually moving closer to the Solar System, so it is expected to increase in brightness slightly over the next 60,000 years, reaching a peak magnitude of -1.

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Sirius A is about twice as massive as the Sun and has an absolute visual magnitude of +1.

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The initially more massive of these, Sirius B, consumed its hydrogen fuel and became a red giant before shedding its outer layers and collapsing into its current state as a white dwarf around years ago.

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Sirius is known colloquially as the "Dog Star", reflecting its prominence in its constellation, Canis Major.

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The heliacal rising of Sirius marked the flooding of the Nile in Ancient Egypt and the "dog days" of summer for the ancient Greeks, while to the Polynesians, mostly in the Southern Hemisphere, the star marked winter and was an important reference for their navigation around the Pacific Ocean.

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Brightest star seen from Earth, Sirius is recorded in some of the earliest astronomical records.

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Sirius served as the body of a "Great Bird" constellation called Manu, with Canopus as the southern wingtip and Procyon the northern wingtip, which divided the Polynesian night sky into two hemispheres.

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The bright stars Aldebaran, Arcturus and Sirius were noted to have moved significantly; Sirius had progressed about 30 arcminutes to the southwest.

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In 1868, Sirius became the first star to have its velocity measured, the beginning of the study of celestial radial velocities.

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Sirius B has a Gaia Data Release 3 parallax with a much smaller statistical margin of error, giving a distance of 8.

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The diameter of Sirius A was first measured by Robert Hanbury Brown and Richard Q Twiss in 1959 at Jodrell Bank using their stellar intensity interferometer.

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Sirius described Sirius as reddish, along with five other stars, Betelgeuse, Antares, Aldebaran, Arcturus and Pollux, all of which are of orange or red hue.

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Sirius cited not only Ptolemy but the poet Aratus, the orator Cicero, and general Germanicus as calling the star red, though acknowledging that none of the latter three authors were astronomers, the last two merely translating Aratus's poem Phaenomena.

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From Earth, Sirius always appears dimmer than Jupiter and Venus, as well as Mercury and Mars at certain times.

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Sirius is visible from almost everywhere on Earth, except latitudes north of 73° N, and it does not rise very high when viewed from some northern cities.

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Sirius can be observed in daylight with the naked eye under the right conditions.

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Sirius is a binary star system consisting of two white stars orbiting each other with a separation of about 20 AU and a period of 50.

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Sirius A is classed as an Am star because the spectrum shows deep metallic absorption lines, indicating an enhancement of its surface layers in elements heavier than helium, such as iron.

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In 1909, Ejnar Hertzsprung was the first to suggest that Sirius was a member of the Ursa Major Moving Group, based on his observations of the system's movements across the sky.

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In 2017, a massive star cluster was discovered only 10 arcminutes from Sirius, making the two appear to be visually close to one other when viewed from the point of view of the Earth.

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Proper name "Sirius" comes from the Latin Sirius, from the Ancient Greek Se?????.

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The WGSN's first bulletin of July 2016 included a table of the first two batches of names approved by the WGSN, which included Sirius for the star a Canis Majoris A It is so entered in the IAU Catalog of Star Names.

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Sirius has over 50 other designations and names attached to it.

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In Iranian mythology, especially in Persian mythology and in Zoroastrianism, the ancient religion of Persia, Sirius appears as Tishtrya and is revered as the rain-maker divinity.

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In Chinese astronomy Sirius is known as the star of the "celestial wolf" in the Mansion of Jing.

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Sirius is mentioned in Surah, An-Najm, of the Qur'an, where it is given the name.

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The star Sirius is one of the most important and sacred stars in Serer religious cosmology and symbolism.

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Sirius is one of the 27 stars on the flag of Brazil, where it represents the state of Mato Grosso.

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Sirius is a frequent subject in science fiction and related popular culture.

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Composer Karlheinz Stockhausen, who wrote a piece called Sirius, is claimed to have said on several occasions that he came from a planet in the Sirius system.

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