mardi 23 septembre 2008

Canis Minor 4


α, Binary, 0.4, and 13, yellowish white and yellow.
Procyon, varied by Procion and Prochion, — Προκύων in the original, — has been the name for this from the earliest Greek records, distinctly mentioned by Aratos and Ptolemy, and so known by all the Latins, with the equivalent Antecanis.
Ulug Beg designated it as Al Shiʽrā al Shāmiyyah, shortened to Al Shāmiyyah; Chrysococca transcribing this into his Low Greek Σιαὴρ Σιαμὴ, and Riccioli into Siair Siami; all of these agreeing with its occasional English title the Northern Sirius. The Alfonsine Tables of 1521 quote it as Aschere, Aschemie et Algomeysa; those of 1545, as prochion & Algomeyla.
It thus has many of its constellation's names; in fact, being the magna pars of it, probably itself bore them before the constellation was formed.
Jacob Bryant insisted that its title came to Greece from the Egyptian Pur Cahen.
Euphratean scholars identify it with the Kakkab Paldara, Pallika, or Palura of the cylinders, the Star of the Crossing of the Water-dog, a title evidently given with some reference to the River of Heaven, the adjacent Milky Way; and Hommel says that it was the Kak-shisha which the majority of scholars apply to Sirius.
Dupuis said that in Hindu fables it was Singe Hanuant; and Edkins that it, or Sirius, was the Persian Vanand.
Reeves' Chinese list gives it as Nan Ho, the Southern River, in which β and η were included.
With the natives of the Hervey Islands it was their goddess Vena.
In astrology, like its constellation, it portended wealth, fame, and good fortune. Procyon culminates on the 24th of February.
Elkin determined its parallax as 0ʺ.341, making its distance from our system about 9 1/2 light years; and, according to Vogel, it is approaching us at a speed of six miles a second. Gould thinks it slightly variable.
Its spectrum is on the border between Solar and Sirian.
It is attended by several minute companions that have long been known; but in November, 1896, Schaeberle of the Lick Observatory discovered a 13th‑magnitude yellowish companion, about 4ʺ.6 away, at a position angle of 318°.8, that may be the one predicted by Bessel in 1844 as explaining its peculiar motion, — a motion resembling that of Sirius, which astronomers had found to be moving in an oval orbit entirely unexplained until the discovery of its companion by Alvan G. Clark in 1862. Barnard, at the Yerkes Observatory in 1898, makes the close companion of Procyon 4ʺ.83 away, at a position angle of 326°.
The period of revolution of this most magnificent system is about forty years, in an orbit slightly greater than that of Uranus, the combined mass being about six times that of our sun and earth, and the mass of the companion equaling that of our sun. Its light is three times greater.

β, 3.5, white.
Gomeisa is from the Ghumaisāʽ of the constellation, changed in the Alfonsine Tables to Algomeyla, and by Burritt to Gomelza.
Occasionally it has been Al Gamus, from another of the Arabians' titles for the whole; and Al Murzim, identical with the name of β Canis Majoris, and for a similar reason, — as if announcing the rising of the brightest star of the figure. The Arabs utilized this, with Procyon, to mark the terminal points of their short Cubit, or Ell, Al Dhirāʽ, their long Cubit being line between Castor and Pollux of Gemini. This same word appears in the title of one of the moon stations in that constellation.

β has some close companions of the 10th and 12th magnitudes.

ζ, θ, ο, and π were the Chinese Shwuy Wei, a Place of Water, a designation that may have been given them from their nearness to the River of Heaven, the Galaxy.

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