Observing the Sky from 40°N
A constellation is a group of celestial bodies, usually stars,
which appear to form a pattern in the sky. Astronomers today still
utilize the term, though the current system focuses primarily on
constellations as grid-like segments of the celestial sphere rather than
as patterns. A star-pattern that is not officially classed as a
constellation is referred to as an asterism. One famous example is the
asterism known as the Big Dipper, a term unused by the International
Astronomical Union (IAU) as the stars are considered part of the larger
constellation of Ursa Major.
The stars within a constellation rarely have any substantial astrophysical relationship to each other, and their apparent proximity when viewed from Earth disguises the fact that they typically lie light years apart. However, there are some exceptions: in the constellation of Ursa Major, the Big Dipper is almost entirely constituted by stars approximate to one another, belonging to a stellar group known as the Ursa Major Moving Group.
https://en.wikibooks.org/wiki/Observing_the_Sky_from_40%C2%B0N/Introduction
The stars within a constellation rarely have any substantial astrophysical relationship to each other, and their apparent proximity when viewed from Earth disguises the fact that they typically lie light years apart. However, there are some exceptions: in the constellation of Ursa Major, the Big Dipper is almost entirely constituted by stars approximate to one another, belonging to a stellar group known as the Ursa Major Moving Group.
https://en.wikibooks.org/wiki/Observing_the_Sky_from_40%C2%B0N/Introduction
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