Constellations

What is a constellation? A constellation is a group of stars that are connected together to form a figure or picture. The term is also used to mean any group of stars visibly related to each other Considered as a fixed configuration or pattern in a particular culture.

The International Astronomical Union (IAU) divides the sky into 88 official constellations with exact boundaries, so that every direction or place in the sky belongs within one constellation.

Northern hemisphere- constellations based upon the constellations of the ancient Greek tradition, containing the signs of the zodiac

A star pattern may be widely known but may not be recognized by the International Astronomical Union; such a pattern of stars is called an asterism. An example is the grouping called the Big Dipper.

The grouping of stars into constellations is essentially arbitrary and random Different cultures have had different constellations, although a few of the more obvious ones tend to recur frequently, e.g., Orion and Scorpius.

In space, most of the stars we see have little or no relation to one another, but can appear to be grouped in the night sky. The stars in a constellation rarely have any astrophysical relationship to each other; they just happen to appear close together in the sky as viewed from Earth; they typically lie many light- years apart in space. One exception to this is the Ursa Major.

Some well-known constellations contain striking and familiar patterns of bright stars. Examples: Orion (containing a figure of a hunter) Leo (containing bright stars outlining the form of a lion) Scorpius (a scorpion) Crux (a cross).

HTM