Ursa Minor and Tucana: Difference between pages

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Ursa Minor (Latin: "Smaller She-Bear", contrasting with Ursa Major), also known as the Little Bear, is a constellation in the northern sky. Like the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, hence the name Little Dipper. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations. Ursa Minor is notable as the location of the north celestial pole, although this will change after some centuries due to the precession of the equinoxes.
[[File:375px-Tucana IAU.svg.png|thumb|Tucana]]
Polaris, the brightest star in the constellation, is a yellow-white supergiant and brightest Cepheid variable star in the night sky, ranging from apparent magnitude 1.97 to 2.00. Beta Ursae Minoris, also known as Kochab, is only slightly fainter, with its apparent magnitude of 2.08. An ageing star that has swollen and cooled to become an orange giant, it has a been found to have a planet orbiting it in 2014. It and magnitude 3 Gamma Ursae Minoris have been called the 'guardians of the pole star'. Three other stellar systems have been discovered to contain planets.


==Babylonian Astronomy==
Tucana is a constellation of stars in the southern sky, named after the toucan, a South American bird. It is one of twelve constellations conceived in the late sixteenth century by Petrus Plancius from the observations of Pieter Dirkszoon Keyserand Frederick de Houtman. Tucana first appeared on a 35-cm (14 in) diameter celestial globe published in 1598 in Amsterdam by Plancius and Jodocus Hondius and was depicted in Johann Bayer's star atlas Uranometria of 1603. French explorer and astronomer Nicolas Louis de Lacaille gave its stars Bayer designations in 1756. The constellations Tucana,Grus, Phoenix and Pavo are collectively known as the "Southern Birds".
Tucana is not a prominent constellation as all of its stars are third magnitude or fainter; the brightest is Alpha Tucanae with an apparent visual magnitude of 2.87. Beta Tucanae is a star system with six member stars, while Kappa is a quadruple system. Five star systems have been found to have exoplanets to date. The constellation contains 47 Tucanae, one of the brightest globular clusters in the sky, and most of the Small Magellanic Cloud.
Irregular in shape, Tucana is bordered by [[Hydrus]] to the east, [[Grus]] and [[Phoenix (Constellation)]] to the north, [[Indus]] to the west and [[Octans]] to the south. Covering 295 square degrees, it ranks 48th of the 88 constellations in size.


In the Babylonian star catalogues, Ursa Minor was known as MAR.GID.DA.AN.NA, the Wagon of Heaven, Damkianna. It appeared on a pair of tablets containing canonical star lists that were compiled around 1000 BC, the MUL.APIN, and was one of the "Stars of Enlil"—that is, the northern sky.The possible origin of its name was its appearing to circle around the north celestial pole.The first mention of Ursa Minor in Greek texts was by Thales of Miletus in approximately 600 BCE.Homer had previously only referred to one "bear", leading to speculation over what he saw the stars of Ursa Minor as, or whether they were recognised at all.
Tucana is one of the twelve constellations established by the Dutch astronomerPetrus Plancius from the observations of the southern sky by the Dutch explorersPieter Dirkszoon Keyser and Frederick de Houtman, who had sailed on the first Dutch trading expedition, known as the Eerste Schipvaart, to the East Indies. It first appeared on a 35-cm (14 in) diameter celestial globe published in 1598 in Amsterdam by Plancius with Jodocus Hondius. The first depiction of this constellation in a celestial atlas was in the German cartographer Johann Bayer'sUranometria of 1603. Both Plancius and Bayer depict it as a toucan.[3][4] De Houtman included it in his southern star catalogue the same year under the Dutch name Den Indiaenschen Exster, op Indies Lang ghenaemt "the Indian magpie, named Lang in the Indies",[5] by this meaning a particular bird with a long beak—ahornbill, a bird native to the East Indies.


Ursa Minor and Ursa Major were related by the Greeks to the myth of Callisto and her son Arcas, both placed in the sky by Zeus. However, in a variant of the story, in which it is [[Boötes]] that represents Arcas, Ursa Minor represents a dog. This is the older tradition, which explains both the length of the tail and the obsolete alternate name of Cynosura (the dog's tail) for Polaris, the North Star.
Cynosura is also described as a nurse of Zeus, honoured by the god with a place in the sky. An alternate myth tells of two bears that saved Zeus from his murderous father Cronus by hiding him on Mt Ida. Later Zeus set them in the sky, but their tails grew long from being swung by the god.In Hungarian mythology the constellation is called 'Little Goncol cart' (Göncöl szekér) after a legendary shaman. (Ursa Major is 'Big Goncol cart.') The shaman's knowledge knew no limit. He invented the cart: His nation was wandering, so the cart was the biggest gift of the Gods to the country. Legends claim he knew everything about the world. Nobody saw his death; his body simply disappeared among the stars.In Inuit astronomy, the three brightest stars—Polaris, Kochab and Pherkad—were known as Nuutuittut "never moving", though the term is more frequently used in the singular to refer to Polaris alone. The pole star was too high in the sky at far northern latitudes to be of use in navigation.Because Ursa Minor consists of seven stars, the Latin word for "North" (i.e. where Polaris points) is septentrio, from septem (seven) and triones (oxen), from seven oxen driving a plow, which the seven stars also resemble. This name has also been attached to the main stars of Ursa Major.


==HGS Session References==  
==HGS Session References==  


HGS Sessions - Clearing [[Hyperspace Phantom Matrix]] - 3/12/2015 <ref>[http://www.energeticsynthesis.com/index.php/forum/52-hgs-discussions-and-q-a-a/60650-hgs-shared-sessions-and-discussion?start=126h HGS Session]</ref>
HGS Sessions - Clearing [[Hyperspace Phantom Matrix]] - 3/12/2015 <ref>[http://www.energeticsynthesis.com/index.php/forum/52-hgs-discussions-and-q-a-a/60650-hgs-shared-sessions-and-discussion?start=126h HGS Session]</ref>HGS Sessions - Clearing [[Tara, Gaia, Cradle of Lyra]]- 3/12/2015 <ref>[http://www.energeticsynthesis.com/index.php/forum/planetary-emancipation-gridwork-peg/60919-documenting-hgs-sessions-for-peg-gridwork?start=42#101308  HGS Session]</ref>


==References==  
==References==