constellation

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See also: Constellations (table)Constellations
Constellation English name Position
R.A.
(hours)
DEC.
(degrees)

Andromeda Andromeda (Chained Lady) 1 +43
Antlia Air Pump 10 −33
Apus Bird of Paradise 16 −75
Aquarius1 Water Bearer 23 −13
Aquila Eagle 20 +4
..... Click the link for more information.

Constellation

(kŏnstĭlā`shən), U.S. frigate, launched in 1797. It was named by President Washington for the constellation of 15 stars in the U.S. flag of that time. The frigate was built to serve against the pirates of the Barbary States, but after the outbreak (1798) of hostilities between the United States and France, it was stationed in Caribbean waters. After the Constellation, commanded by Thomas Truxtun, encountered and captured (Feb., 1799) the vessel Insurgente, it won (Feb., 1800) a hard-fought victory over another French frigate, the Vengeance. The Constellation was blockaded at Norfolk, Va. during the War of 1812, but further victories followed in the Mediterranean in 1815. Rebuilt in 1853–55, the Constellation was used against Confederate commerce cruisers in the Civil War and later served (1873–93) as a training ship at Annapolis, Norfolk, and Philadelphia. It became the ship with the longest period of service in the navy when it saw duty as flagship of the U.S. Atlantic fleet during World War II. It is preserved at Baltimore.

Bibliography

See study by H. I. Chapelle and L. D. Polland (1970).


See also: Constellations (table)Constellations
Constellation English name Position
R.A.
(hours)
DEC.
(degrees)

Andromeda Andromeda (Chained Lady) 1 +43
Antlia Air Pump 10 −33
Apus Bird of Paradise 16 −75
Aquarius1 Water Bearer 23 −13
Aquila Eagle 20 +4
..... Click the link for more information.

constellation,

in common usage, group of stars that appear to form a configuration in the sky; properly speaking, a constellation is a definite region of the sky in which the configuration of stars is contained. Identifiable groupings of bright stars have been recognized and named since ancient times, the names corresponding to mythological figures (e.g., Perseus, Andromeda, Hercules, Orion), animals (e.g., Leo the Lion, Cygnus the Swan, Draco the Dragon), or objects (e.g., Libra the Balance, Corona the Crown). Ptolemy listed 48 constellations in his Almagest (2d cent. A.D.).

As systematic observations were extended to the entire southern sky from the 17th cent. on, more constellations were added to the list by J. Bayer, N. L. de Lacaille, and others. For example, Ptolemy's 48th constellation, Argo Navis, representing a ship, was divided into four smaller constellations corresponding to different parts of the ship. The final list consists of 88 constellations, each associated with a definite region of the sky. Thus, the entire celestial spherecelestial sphere,
imaginary sphere of infinite radius with the earth at its center. It is used for describing the positions and motions of stars and other objects. For these purposes, any astronomical object can be thought of as being located at the point where the line of sight
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 is divided according to a plan prepared by Eugene Delporte, with the boundaries fixed by international agreement in 1930, along lines of right ascensionright ascension,
in astronomy, one of the coordinates in the equatorial coordinate system. The right ascension of a celestial body is the angular distance measured eastward from the vernal equinox along the celestial equator to its intersection with the body's hour circle.
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 and declinationdeclination,
in astronomy, one of the coordinates in the equatorial coordinate system. The declination of a celestial body is its angular distance north or south of the celestial equator measured along its hour circle.
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 (see equatorial coordinate systemequatorial coordinate system,
the most commonly used astronomical coordinate system for indicating the positions of stars or other celestial objects on the celestial sphere. The celestial sphere is an imaginary sphere with the observer at its center.
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). The 12 constellations located along or near the eclipticecliptic
, the great circle on the celestial sphere that lies in the plane of the earth's orbit (called the plane of the ecliptic). Because of the earth's yearly revolution around the sun, the sun appears to move in an annual journey through the heavens with the ecliptic as its
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, the apparent path of the sun through the heavens, are known as the constellations of the zodiaczodiac
[Gr. zoion=animal], in astronomy, zone of the sky that includes about 8° on either side of the ecliptic. The apparent paths of the sun, the moon, and the major planets all fall within this zone.
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; the remaining constellations are officially classified as northern (28 constellations) or southern (48 constellations).

The table entitled ConstellationsConstellations
Constellation English name Position
R.A.
(hours)
DEC.
(degrees)

Andromeda Andromeda (Chained Lady) 1 +43
Antlia Air Pump 10 −33
Apus Bird of Paradise 16 −75
Aquarius1 Water Bearer 23 −13
Aquila Eagle 20 +4
..... Click the link for more information.
 lists the constellations according to their official Latin names, with the English equivalents and the approximate positions given. In some cases, the English name for a constellation is not an exact translation of the Latin; e.g., the English name for Pictor reflects the fact that the figure in the constellation is not the painter himself but his easel. Certain familiar star groups, or asterisms, are not listed as constellations because they form only part of a larger constellation; the Big Dipper and Little Dipper are parts of the constellations Ursa Major and Ursa Minor, and the Northern Cross is part of Cygnus.

Bright stars within a constellation are designated according to a system originated by Bayer in 1603: the brightest star is designated by the Greek letter alpha followed by the genitive form of the Latin name for the constellation, the second brightest star by beta, and so on, with Roman letters and pairs of Roman letters being used after the Greek letters have all been assigned. For example, the brightest star in Taurus, Aldebaran, is designated Alpha Tauri, the second brightest, Elnath, is designated Beta Tauri, and so on. The alphabetical order does not always indicate the stars' relative brightness: in a few cases, e.g., Ursa Major, the assignment of a Bayer name is according to position rather than brightness.

constellation

(kon-stĕ-lay -shŏn) Any of the 88 areas into which astronomers have divided the whole of the northern and southern hemispheres of the sky (or celestial sphere). Every star, galaxy, nebula, or other celestial body lies within, or sometimes overlaps, the boundaries of one of the constellations. These boundaries were established unambiguously by the International Astronomical Union in 1930 along arcs of right ascension and declination for the epoch 1875, Jan. 1.

Originally the constellations had no fixed limits but were groups of stars considered by early civilizations to lie within the imagined outlines of mythological heroes, creatures, and other forms. In the Almagest , Ptolemy, in about ad 140, listed 48 constellations that were visible from the Mediterranean region. Their names were mostly derived from Greek and Roman mythology, which sought to explain their presence in the sky, but a few, such as Leo, the Lion, may be of much earlier origin. During the 16th, 17th, and 18th centuries many new groupings were identified and named (and several later discarded), especially in the previously uncharted regions of the southern hemisphere. These new groupings appeared principally in star atlases published by Bayer and Hevelius in the 17th century and Lacaille in the 18th. Since then further additions have proved unacceptable.

The constellations seen on any clear night depend on the latitude of the observer and change with the time of year and time of night. If, for a particular latitude, ⊂, the stars are circumpolar stars (never set), they will be visible on every night of the year. Circumpolar stars are those with declinations greater than 90 – ⊂°. Other stars never rise above the horizon at all: for observers in the northern hemisphere, these are the ones that have declinations beyond ⊂ – 90°; for observers in the southern hemisphere, they are the ones with declinations of ⊂ + 90° (note that southern latitudes, like southern declinations, are taken to be negative for these calculations). The remaining stars can be seen only when they are above the horizon during the night, a star rising earlier, on average, by about two hours per month.

Each constellation bears a Latin name, as with Canis Major, the genitive form of which is used with the appropriate letter or number for the star name (see stellar nomenclature), as with Alpha Canis Majoris. For simplification the three-letter abbreviations for the constellations are more usually used, as with CMa. See Table 5, backmatter.

Enlarge picture
An image of a Denderah constellation map, sometimes called the Denderah zodiac. The original is housed in the Louvre. Reproduced by permission of Fortean Picture Library.

Constellation

(religion, spiritualism, and occult)

A constellation is a collection of stars that the ancients grouped together, identified with a figure from mythology, and named after that figure. In astrology, the names of the various signs of the zodiac are taken from 12 constellations intersected by the ecliptic. The untutored eye has a difficult time discerning the relationship between these star groups and the figures they are said to represent: Unlike the ancients, who gazed upon a sky filled with legends, heroes, and heroines, we moderns look up to see only a confused mass of tiny lights.

Constellation

 

in modern astronomy, any one of the sections into which the celestial sphere is divided in order to facilitate orientation in the stellar sky. In antiquity, however, constellations were the symbolic figures formed by bright stars. The most important constellations bore names borrowed from mythology, for example, Hercules and Perseus, or from everyday life, such as Libra and Lyra. The grouping of stars into constellations has no scientific significance. The entire sky is divided into 88 constellations, which were officially designated by the International Astronomical Union in 1930. (SeeSTELLAR SKY for a list of the constellations.)

constellation

[‚kän·stə′lā·shən]
(astronomy)
Any one of the star groups interpreted as forming configurations in the sky; examples are Orion and Leo.
Any one of the definite areas of the sky.

constellation

1. any of the 88 groups of stars as seen from the earth and the solar system, many of which were named by the ancient Greeks after animals, objects, or mythological persons
2. Psychoanal a group of ideas felt to be related