dimanche 5 octobre 2008

Hercules 9

α, Double and both irregularly variable, 3.1 to 3.9 and 5 to 7, orange red and bluish green.

Ras Algethi, also Ras Algathi, on Malby's globe Ras Algothi, is from Al Rās al Jāthīyy, the Kneeler's Head; but it often is Ras Algeti, sometimes Ras Algiatha, and the Standard Dictionary has Ras Algetta. It was Rasacheti with Chilmead. Riccioli's Ras Elhhathi and Ras Alhathi probably came from Ras Alheti of the first three editions of the Alfonsine Tables; but in the 4th edition very incorrectly appeared Rasaben for both the star and the constellation, probably taken from the neighbouring Al Rās al Thuʽbān of Draco; — all Arabian translations of the Greek names.
The nomads' title for it was Al Kalb al Rāʽi, the Shepherd's Dog, that our α shared with the adjoining lucida of Ophiuchus, 5° distant.
The Chinese called it Ti Tso, the Emperor's Seat; and Tsin.
Some small stars in Hercules, near α, were included with ι and κ Ophiuchi in the asterism Ho, one of the measures of China.
This is a beautiful pair, but apparently not binary, for there has been no certain change in the last century. The components are 4ʺ.8 apart, at a position angle of 119°. Its variability, discovered by Sir William Herschel in 1795, is now described by Chandler as shown by "very irregular oscillations in periods of two to four months." It is one of the most noted of Secchi's 3d type with banded spectra.
α culminates on the 23d of July.

β, 2.8, pale yellow.

Korneforos and Kornephoros are from the Κορυνηφόρος which we have seen applied to the whole figure. Burritt has Kornephorus vel Rutilicus, perhaps the diminutive of rutilus, "golden red," or "glittering," an adjective applied to Arcturus; but this term is by no means appropriate for β. The Arabo-Latin Almagest of 1515 reads rutillico, adding propinque cillitico, this last unintelligible unless explained by the Basel edition of 1551 as penes axillam seu scapulam; so that we may perhaps consider the alternative title to be from the barbarism used to show the star's position on the shoulder of the figure. Indeed, Bayer said of it, Rutilicum barbari dicunt. Ideler, however, asserted his belief that it was from rutellum, the diminutive of rutrum, a sharp instrument of husbandry or war, in Roman times, that Hercules in some early representations, especially on the Arabic globes, is carrying. The Century Cyclopedia gives Rutilico as a rarely used name.
β was the Chinese Ho Chung, In the River, while the 4th‑magnitude γ was Ho Keen, Between the River.
Its spectrum is like that of the sun, and the star is approaching our system at the rate of about 22 miles a second.
ζ, 3.1 and 6.5, is a remarkable binary with a period of only 34 1/2 years, the distance between the stars ranging from 0ʺ.6 to 1ʺ.7. According to Belopolsky, it is approaching us at the rate of nearly forty-four miles a second, — the greatest velocity of approach or recession so far ascertained.
θ, 4.1, with adjacent small stars, was Tien Ke, Heaven's Record.
κ, Double, 4.8 and 7, light yellow and pale garnet.

Marfak, Mirfak, Marsia, Marfic, and Marsic are all found for this star, — as for λ Ophiuchi; but it properly is Marfik, from Al Marfiḳ, the Elbow; the titles written with the letter s probably coming from early confusion with the letter f. The Dorians similarly called it Κύβιτον, the Elbow.
In China, with two other stars near by, it was Tsung Tsing, an Ancestral Star.
Ptolemy and the Arabian astronomers located it on the right elbow, but Smyth on the left; Heis places it in the right hand, as did Bayer; while Burritt has Marsic in the proper place, but letters it χ.

λ, 4.8, deep yellow.

Masym, Maasym, Maasim, Mazym, Mazim, and Masini are from the Arabic Miʽṣam, the Wrist, although Ptolemy as well as most of the stellar map-makers located ο on that part of the figure; but Bayer, probably by an oversight, gave the title to λ, not far from the left shoulder, and hence the mistake which still survives. Burritt applied Masym to this lettered p245star at the elbow, and duplicated it at the one on the hand, omitting the letter; but this title had appeared in the Latin Almagest of 1515 and the Alfonsine Tables of 1521, not as a proper name, but simply indicative of the position of the star ο, which, though now unnamed, should bear that title instead of λ. The same word is used in those works to describe the positions of θ and η Aurigae in the similar location, but is there written Mahasim. The Century Cyclopedia, by a misprint for λ, uses Masym for χ Herculis in the left hand of the giant.
λ also was Chaou, one of the early feudal states of China.

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