mercredi 1 octobre 2008

Draco 9

δ, 3.1, deep yellow,

is the Nodus secundus of several catalogues, as marking the 2d of the four Knots, or convolutions, in the figure of the Dragon.
Al Tizini called it Al Tāis, the Goat, as the prominent one of the quadrangle, δ, π, ρ, and ε, which bore this title at a late period in Arabic indigenous astronomy; although that people generally gave animal names only to single stars. The Jais, which is found in various lists, maps, and globes, would seem to be a typographical error, or an erroneous transliteration of the original Arabic. δ also may have been one of Firuzabadi's two undetermined stars Al Tayyasān, the Two Goatherds.
p210 δ, ε, π, ρ, and σ were the Chinese Tien Choo, Heaven's Kitchen.
ζ, a 3d‑magnitude, was Al Dhiʽbah, that we have also seen for α.
The Chinese knew it as Shang Pih, the Higher Minister.
Half-way between it and δ, within 7ʹ of the planetary nebula NGC 6543, is the north pole of the ecliptic; the south pole being in the head of Dorado. Denning considers ζ the radiant point of the meteor streams of the 19th of January and of the 28th of March.
η, a double 2d- and 8th‑magnitude, deep yellow and bluish star, was known in China as Shang Tsae, the Minor Steward.
The components are about 5ʺ apart, and the position angle is 143°.1.
ζ and η together were Al Dhīʼbain, the Duo Lupi of early works, the Two Hyaenas or Wolves, lying in wait for the Camel's Foal, the little star Al Rubaʽ, protected by the Mother Camels, the larger stars in our Draco's Head. They also were Al ʽAuhaḳān, the Two Black Bulls, or Ravens, the Arabic signifying either of these creatures; but this last word likewise appears for ω and f, and for χ and ψ; all of these titles being from Arabia's earliest days.
θ, a 4.3‑magnitude, is Hea Tsae, the Lowest Steward; while the smaller stars near it were Tien Chwang.
ι, 3.6, orange.

Smyth mentioned this as Al Ḍhibaʼ of the Dresden globe and of Ulug Beg, but Kazwini had called it Al Dhīḣ, the Male Hyaena, from which comes Ed Asich, its usual title and, the Eldsich of the Century Cyclopedia.
In China it was Tsao Choo, the Left Pivot.
It marks the radiant point of the Quadrantid meteors of the 2d and 3d of January, so called from the adjacent Mural Quadrant.
A 9th‑magnitude pale yellow companion is 2ʹ distant.

λ, 4.1, orange.

Giansar and Giauzar are variously derived: either from Al Jauzāʼ, — a little star is in close proximity, — or from Al Jauzah, the Central One, as it is nearly midway between the Pointers and Polaris; or, and still better, from the Persian Ghāuzar, — Al Bīrūnī's Jauzahar of Sāsānian origin, — the Poison Place, referring to the notion that the nodes, or points where the moon crosses the ecliptic, were poisonous because they "happened to be called the Head and Tail of the Dragon." This singular idea descended into comparatively modern times, and, although these points are far removed p211 from Draco, still obtains in the name for λ. Juza is another popular title.
It also has been known as Nodus secundus, the Second Knot, possibly because thus located on some drawings; yet it is far removed from δ, which usually bears that name.
In China it was Sang Poo, or Shaou Poo.
Although the last lettered star in the figure, it lies at a considerable distance from the end, as figured on the atlases of Heis and Argelander.
μ, Binary, 5 and 5.1, brilliant white and pale white.

Al Rāḳis, from Ulug Beg's catalogue, turned into Arrakis and Errakis, generally has been thought to signify the Dancer, perhaps to the neighboring Lute-player, the star β; but here probably the Trotting Camel, one of the group of those animals located in this spot. Ideler added for it Al Rāfad, the Camel Pasturing Freely, that the original, differently pointed, may mean. The little star in the centre of the group of Camels, β, γ, μ, ν, and ξ, is named Al Rubaʽ on the Borgian globe, although almost invisible; but did not appear in the catalogues till Piazzi's time, except with Julius Schiller in his Coelum Stellatum Christianum of 1627, where it is the 37th star in his constellation of the Holy Innocents.
Assemani mentioned μ as Al Caʽab, the Little Shield or Salver, but gave no reason for this, and its inappropriateness renders the claim very doubtful.
In modern drawings it marks the nose or tongue of Draco.
The components are 2ʺ.5 apart, with a position angle of 165°; and their period is long, although not yet accurately determined.
ν, on the Dragon's head, already mentioned in connection with β, γ, μ, and ξ, is an interesting double for a small telescope. The components are each of 4.6 magnitude, about 62ʺ apart, with a position angle of 313°.
According to Wagner's determination of the parallax, — not yet, however, confirmed, — they are near neighbors to us, at a distance of about eleven light years.
ξ, 3.8, yellow,

was one of the Herd of Camels; but its modern individual name, Grumium, is the barbarism found for it in the Almagest of 1515, an equivalent of γένυς used by Ptolemy for the Dragon's under jaw. The word is now seen in the Italian grugno and the French groin.
Bayer followed Ptolemy in calling the star Genam.
p212 Proctor thought that it marked Draco's darted tongue in the earliest representations of the figure, — unless ι Herculis were such star; while Denning considers it the radiant point of the meteor stream seen about the 29th of May, — the Draconids.
σ, 6.5, in the second coil northeast from δ, is Alsafi, corrupted from Athāfi, erroneously transcribed from the Arabic plurarl Athāfiyy, by which the nomads designated the tripods of their open-air kitchens; one of these being imagined in σ, τ, and υ. Uthfiyyah is the singular form. It probably is one of the nearest stars to our system, — about thirteen light years away according to Brunowski's unconfirmed determination.
φ, a 4th‑magnitude double, was the Chinese Shaou Pih, the Minor Minister; and χ, of slightly greater brilliancy, was Kwei She.

ψ1 and ψ2, 4.3 and 5.2, pearly white and yellow.

Dsiban, from Al Dhībain (the Arabs' title for ζ and η), has been given by some to this pair, and Lach thought that with χ it also was Al ʽAuhaḳān, which we similarly find for ζ and η.
In China it was Niu She, the Palace Governess, or a Literary Woman.
The components of ψ1 are about 30ʺ apart, with a position angle of 15°.
ω, 4.9, and f, 5.1.

These dim stars, between ζ and the group φ, χ, and ψ, were Al Aṭhfār al Dhīb, the Hyaena's claws, stretched out to clutch the Camel's Foal. They thus appear with Ulug Beg and on the Dresden globe; but elsewhere occasionally were known as Al ʽAuhaḳān, a designation shared with ζ and η, and with φ and χ. They also sometimes were Al Dhīḣ, the Wolf.
There seems to be confusion, and some duplication, in the nomenclature of Draco's stars, but their many titles show the great attention paid to the constellation in early days.

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