lundi 29 septembre 2008

Gemini 14

γ, 2.2, brilliant white.

Almeisan, Almisan, Almeisam, and Almisam are from Al Maisan, the Proudly Marching One, its early Arabic name, which Al Firuzabadi, however, said was equally applicable to any bright star.
Riccioli called it Elhenaat, but Alhena is now generally given to it, from Al Hanʽah, the 4th manzil, γ, μ, ν, η, and ξ, in the feet of the Twins. This word, usually translated a Brand, or Mark, on the right side of a camel's, or horse's neck, was defined by Al Bīrūnī as Winding, as though the stars of this station were winding around each other, or curving from the central star; and they were Al Nuḥātai, the dual form of Al Nuḥāt, a Camel's Hump, itself a curved line. Some Arabic authority found in them, with χ1 and χ2 of Orion, the Bow with which the Hunter is shooting at the Lion.
In Babylonia γ marked the 10th ecliptic constellation, Mash-amshu-sha-Risū, the twins of the Shepherd (?), and, with η, probably was Mas-tab-ba-tur-tur, the Little Twins; and, with η, μ, ν, and ξ, all in the Milky Way, may have been the Babylonian lunar mansion Khigalla, the Canal, and the equivalent Persian Rakhvad, the Sogdian Ghathaf, and the Khorasmian Gawthaf.
δ, Double, 3.8 and 8, pale white and purple.

Wasat and Wesat are from Al Wasat, the Middle, i.e. of the constellation; but some have referred this to the position of the star very near to the ecliptic, the central circle.
In China it was Ta Tsun, the Great Wine-jar.
The components are 7ʺ apart, with a position angle of 203°, and may form a binary system.
Just north of δ lies the radiant point of the Geminids visible early in October; another stream of meteors bearing the same title appearing from the northeastern border of the constellation and at its maximum on the 7th of December.
ε, Double, 3.4 and 9.5, brilliant white and cerulean blue.

Mesbuta is from Al Mabsuṭāt, the Outstretched, from its marking the extended paw of the early Arabic Lion, but now it is on the hem of Castor's tunic. Burritt had it Melucta in his Geography, and Mebusta in his Atlas; Professor Young, following English globes, has Meboula; and elsewhere we find Menita, Mesoula, and Mibwala.
ε, δ, λ, and others near by, were the Chinese Tung Tsing.

ζ, Variable, 3.7 to 4.5, pale topaz.

Mekbuda is from Al Maḳbūḍah, Contracted, the Arabic designation for the drawn-in paw of the ancient Asad; but some, with less probability, derive it from Al Mutakabbidah, a Culminating Star.
Its variations, discovered by J. F. Julius Schmidt at Athens in 1847, have a period of about ten days, but Chandler says that definitive investigation are not completed. Lockyer thinks it also a spectroscopic binary.
η, Binary and variable, 3.2 to 3.7, and 9.

Propus is from the Πρόπους of Hipparchos and Ptolemy, indicating its position in front of Castor's left foot, and is its universal title, with the equivalent Praepes. Riccioli wrote it Πρόπος, and Flamsteed gave both Πρόπους and Propus; but Tycho had applied this last to the star Fl. 1 among the extras of Gemini. This position of η similarly made it the Pish Pai of the Persians.
Bassus and Hyginus said Tropus, Turn, referring to the apparent turning-point the sun's course at the summer solstice, which now is more precisely marked by the star y just eastward from η; and Flamsteed also had Τρόπος.
Flammarion's assertion that Hipparchos knew η as a distinct constellation, Propus, does not seem well founded.
Tejat prior is from Al Taḥāyī, an anatomical term of Arabia by which it was known in early days; a name also applied to stars in the head of Orion. The Arabs included it with γ and μ in their Nuḥātai; the Chinese knew it as Yuë, a Battle-ax; and in Babylonia it marked the 8th ecliptic constellation, Maru-sha-pu-u-mash-mashu, the Front of the Mouth of the Twins.
It portended lives of eminence to all born under its influence.
The variability of η was discovered by Schmidt in 1865, and its period is now considered as 229‑231 days; in 1881 Burnham found it double, the components 1ʺ.08 apart, and likely to prove an interesting binary system.
Near this star Sir William Herschel discovered the planet Uranus on the 13th of March, 1781. He thought it a comet, and its discovery as such was communicated to the Royal Astronomical Society on the 26th of April. Its true nature, however, first suspected by Maskelyne, was announced in the succeeding year by Lexell of Saint Petersburg and by La Place; and Herschel then published it on the 7th of November, 1782, as the Georgium Sidus, thus following Galileo, who, till he knew their true nature, had named Jupiter's satellites Sidera Cosmiana and Sidera Medicea, after his patron the 2d Cosmo di Medici, and Tardé, who had called the sun-spots Borbonica Sidera. Continental astronomers designated the planet as Herschel, and this in a much varied orthography, strangely erroneous considering the fame of its discoverer. We find it thus with La Lande in 1792; indeed, Herschel appeared as an alternative title in our text-books as late as fifty years ago; but Bode suggested the present Uranus to conform to the mythological nomenclature of the other planets, and because the name of the oldest god was specially applicable to the oldest — as the most distant — body then known in our system.
Uranus, however, had been observed and noted as a star twenty-two times previously by various observers; these are called "the ancient observations"; and Miss Clerke writes: "There is, indeed, some reason to suppose that he had been detected as a wandering orb by savage 'watchers of the skies' on the Pacific long before he swam into Herschel's ken."
The 4th‑magnitude θ, and ι, ν, τ, and φ, collectively were Woo Chow Shih, or Woo Choo How, the Seven Feudal Princes of China.
ι is Propus in the Standard Dictionary, although it lies between the shoulders of the Twins.
μ, Double, 3.2 and 11, crocus yellow and blue,

occasionally has been known as Tejat posterior, and sometimes as Nuḥātai, from the manzil of that title of which it formed a part.
The Century Dictionary and Cyclopedia apply to it the Pish Pai seen for η, yet appropriate enough for this similarly situated star; but in Flamsteed's edition of Tycho's catalogue we distinctly read of it, dicta Calx, the Heel.
It marked the 9th ecliptic constellation of Babylonia as Arkū-sha-pu-u-mash-mashu, the Back of the Mouth of the twins.
In China it was included with Castor and others in the sieu Tsing.
The components are 80ʺ apart, at a position angle of 79°.
ξ, a 4th‑magnitude, was Al Bīrūnī's Al Zirr, the Button.
χ, a 5th‑magnitude, with μ Cancri, was the Chinese Tseih Tsing, Piled-up Fuel.

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