Northern celestial hemisphere

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A star chart of the entire Northern Sky, centered on the north celestial pole North Hemisphere.png
A star chart of the entire Northern Sky, centered on the north celestial pole

The northern celestial hemisphere, also called the Northern Sky, is the northern half of the celestial sphere; that is, it lies north of the celestial equator. This arbitrary sphere appears to rotate westward around a polar axis due to Earth's rotation.

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At any given time, the entire Northern Sky is visible from the geographic North Pole, while less of the hemisphere is visible the further south the observer is located. The southern counterpart is the southern celestial hemisphere.

Astronomy

In the context of astronomical discussions or writing about celestial cartography, the northern celestial hemisphere may be referred to as the Northern Hemisphere.

For celestial mapping, astronomers may conceive the sky like the inside of a sphere divided into two halves by the celestial equator. The Northern Sky or Northern Hemisphere is therefore the half of the celestial sphere that is north of the celestial equator. Even if this geocentric model is the ideal projection of the terrestrial equator onto the imaginary celestial sphere, the northern and southern celestial hemispheres are not to be confused with descriptions of the terrestrial hemispheres of Earth itself.

Observation

Of the modern 88 constellations, 36 lie predominantly within the northern celestial hemisphere, with 28 completely on the northern hemisphere. The other 8 constellations (Aquila, Canis Minor, Leo, Monoceros, Orion, Pisces, Serpens Caput, and Taurus) lie in some piece on the southern hemisphere. [1] The northern constellations are: [2]

The North Star, the brightest star in the constellation Ursa Minor, has been used extensively throughout history to find north due to its brightness and proximity to north celestial pole.

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<span class="mw-page-title-main">Constellation</span> Group of stars on the celestial sphere

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<span class="mw-page-title-main">Flamsteed designation</span> Star identification system

A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England. They are named for John Flamsteed who first used them while compiling his Historia Coelestis Britannica.

<span class="mw-page-title-main">Taurus (constellation)</span> Zodiac constellation straddling the celestial equator

Taurus is one of the constellations of the zodiac and is located in the northern celestial hemisphere. Taurus is a large and prominent constellation in the Northern Hemisphere's winter sky. It is one of the oldest constellations, dating back to the Early Bronze Age at least, when it marked the location of the Sun during the spring equinox. Its importance to the agricultural calendar influenced various bull figures in the mythologies of Ancient Sumer, Akkad, Assyria, Babylon, Egypt, Greece, and Rome. Its old astronomical symbol is (♉︎), which resembles a bull's head.

<span class="mw-page-title-main">Galactic coordinate system</span> Celestial coordinate system in spherical coordinates, with the Sun as its center

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<span class="mw-page-title-main">Chinese constellations</span> Groupings used in Chinese astrology

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<span class="mw-page-title-main">Circumpolar star</span> Star that never sets due to its apparent proximity to a celestial pole

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<span class="mw-page-title-main">Winter Triangle</span> Asterism

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<span class="mw-page-title-main">IAU designated constellations</span> Constellations recognized by the International Astronomical Union

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<span class="mw-page-title-main">Pole star</span> Visible star that is nearly aligned with Earths axis of rotation

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<span class="mw-page-title-main">Asterism (astronomy)</span> Pattern of stars recognized on Earths night sky

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<span class="mw-page-title-main">Winter Hexagon</span> Evening sky asterism with vertices at Rigel, Aldebaran, Capella, Pollux, Procyon, and Sirius

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<span class="mw-page-title-main">Outline of astronomy</span>

The following outline is provided as an overview of and topical guide to astronomy:

<span class="mw-page-title-main">Constellation family</span> Designated common star constellations

Constellation families are collections of constellations sharing some defining characteristic, such as proximity on the celestial sphere, common historical origin, or common mythological theme. In the Western tradition, most of the northern constellations stem from Ptolemy's list in the Almagest, and most of the far southern constellations were introduced by sailors and astronomers who traveled to the south in the 16th to 18th centuries. Separate traditions arose in India and China.

Gould designations for stars are similar to Flamsteed designations in the way that they number stars within a constellation in increasing order of right ascension. Each star is assigned an integer, followed by " G. ", and then the Latin genitive of the constellation it lies in. See 88 modern constellations for a list of constellations and the genitive forms of their names.

This table lists those stars/objects which have Flamsteed designations by the constellation in which those stars/objects lie. The name given is that of the article if it does not reflect the Flamsteed designation. Some articles are linked twice, in cases where the star has been assigned two different Flamsteed designations, usually as noted in different constellations.

<i>Uranias Mirror</i> Set of 32 astronomical star chart cards

Urania's Mirror; or, a view of the Heavens is a set of 32 astronomical star chart cards, first published in November 1824. They are illustrations based on Alexander Jamieson's A Celestial Atlas, but the addition of holes punched in them allow them to be held up to a light to see a depiction of the constellation's stars. They were engraved by Sidney Hall, and were said to be designed by "a lady", but have since been identified as the work of the Reverend Richard Rouse Bloxam, an assistant master at Rugby School.

<span class="mw-page-title-main">Southern celestial hemisphere</span> Southern half of the celestial sphere

The southern celestial hemisphere, also called the Southern Sky, is the southern half of the celestial sphere; that is, it lies south of the celestial equator. This arbitrary sphere, on which seemingly fixed stars form constellations, appears to rotate westward around a polar axis as the Earth rotates.

References

  1. "International Astronomical Union | IAU". www.iau.org. Retrieved 2024-02-13.
  2. "Northern Constellations – Constellation Guide". www.constellation-guide.com. Retrieved 2024-02-13.

See also