constellations
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. 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). The modern system of constellations used in astronomy focuses primarily on constellations as grid-like segments of the celestial sphere rather than as patterns, while the term for a star-pattern isasterism. For example, the asterism known as the Big Dipper corresponds to the seven brightest stars of the larger 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 celestial equator are circumpolar constellations. In the northern latitudes, the informal term equatorial constellation has sometimes been used for constellations that lie to the south of the circumpolar constellations. The current list of 88 constellations recognized by the International Astronomical Union since 1922 is based on the 48 listed byPtolemy in his Almagest in the 2nd century. The stars in the sky are divided into 88 constellations.
The brightest constellation is Crux (the Southern Cross). The constellation with the greatest number of visible stars in it is Centaurus (the Centaur - with 101 stars). The largest constellation is Hydra (The Water Snake) which extends over 3.158% of the sky.
There are also asterisms, smaller apparent star patterns within a constellation, like the Big Dipper (in Ursa Major), the Little Dipper (in Ursa Minor), Keystone (in Hercules), and the Pleiades (in Taurus).
Ancient Near East[edit]
The
The brightest constellation is Crux (the Southern Cross). The constellation with the greatest number of visible stars in it is Centaurus (the Centaur - with 101 stars). The largest constellation is Hydra (The Water Snake) which extends over 3.158% of the sky.
There are also asterisms, smaller apparent star patterns within a constellation, like the Big Dipper (in Ursa Major), the Little Dipper (in Ursa Minor), Keystone (in Hercules), and the Pleiades (in Taurus).
Ancient Near East[edit]
The