Constellations

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Constellation
From Wikipedia, the free encyclopedia

In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms (which themselves are generally referred to in non-technical language as "constellations"), which are patterns formed by prominent stars within apparent proximity to one another on Earth's night sky. There are 88 standard constellations recognized by the International Astronomical Union (IAU) since 1922. The majority of these go back to the 48 constellations defined by Ptolemy in his Almagest (2nd century). The remaining ones were defined in the 17th and 18th century; the most recent ones are found on the southern sky, defined in Coelum australe stelliferum by Nicolas Louis de Lacaille (1763). There are also numerous historical constellations not recognized by the IAU, or constellations recognized in regional traditions of astronomy or astrology, such as Chinese, Hindu and Australian Aboriginal.

Contents
1 Terminology 2 History 2.1 Ancient Near East 2.2 Graeco-Roman 2.3 Classical Chinese constellations 2.4 Early Modern era 3 IAU constellations 4 Asterisms 5 Dark cloud constellations 6 See also 7 Notes 8 Further reading 8.1 Mythology, lore, history, and archaeoastronomy 8.2 Atlases and celestial maps 8.3 Catalogs 9 External links

The constellation Orion is one of the mos in the night sky.

Terminology

The Late Latin term constellātiō can be translated as "set with stars". The term was first used in astrology, of asterisms that supposedly exerted influence, attested in Ammianus (4th century). term was used from the 14th century, also in astrology, of conjunctions of planets. The modern astronomical sense of "area of the celestial sphere around a specific asterism" dates to the mid

Colloquial usage does not distinguish the senses of "asterism" and "area surrounding an asterism". The modern system of constellations used in astronomy focuses primarily on constellations a segments of the celestial sphere rather than as patterns, while the term for a star-pattern is asterism. For example, the asterism known as the Big Dipper corresponds to the seven brightest sta IAU constellation of Ursa Major.

The term circumpolar constellation is used for any constellation that, from a particular latitude on Earth, never sets below the horizon. From the north pole, all constellations north of the circumpolar constellations. In the northern latitudes, the informal term equatorial constellation has sometimes used for constellations that lie to the south of the circumpolar constellations. the definition, equatorial constellations can include those that lie entirely between declinations 45° north and 45° south,[2] or those that pass overhead between the tropics of Cancer and Capr generally include all constellations that intersect the celestial equator.

History
Further information: Former constellations and Star Names: Their Lore and Meaning

The current list of 88 constellations recognised by the International Astronomical Union since 1922 is based on the 48 listed by Ptolemy in his Almagest in the 2nd century.[3][4] Ptolemy's ca informed by Eudoxus of Cnidus, a Greek astronomer of the 4th century BC who introduced earlier Babylonian astronomy to the Hellenistic culture. Of the 48 constellations listed by Ptolemy shown to have a much longer history, reaching back into at least the Late Bronze Age. This concerns the zodiacal constellations in particular.

Ancient Near East
See also: Babylonian star catalogues and MUL.APIN

The oldest catalogues of stars and constellations are from Old Babylonian astronomy, beginning in the Middle Bronze Age. The numerous Sumerian names in these catalogues suggest that the older, but otherwise unattested, Sumerian traditions of the Early Bronze Age. The classical Zodiac is a product of a revision of the Old Babylonian system in later Neo-Babylonian astronomy BC. Knowledge of the Neo-Babylonian...
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