mercredi 24 septembre 2008

Sagittarius 11

α, 4.
This is Rukbat, but variously written Rucba, Rucbah, Rukbah, and Rucbar, from Ulug Beg's Rukbat al Rāmī, the Archer's Knee; in some early books it is Al Rāmī, the Archer himself. The Standard Dictionary has Ruchbar ur Ranich.
The Euphratean Nibat Anu, already alluded to, may be for this, or for some other of the chief components of the constellation; perhaps for ε if, in early days, that star was comparatively as bright as now.

β1, Double, 3.8 and 8, and β2, 4.4.
Arkab and Urkab are from Al ʼUrḳūb, translated by Ideler as the Tendon uniting the calf of the leg to the heel, and this coincides with their location in the figure on modern maps, as well as with their Euphratean title Ur-ner‑gub, the Sole of the Left Foot; but Al Sufi and the engraver of the Borgian globe assigned these stars to the rear of the horse's body.
Kazwini knew α and the two betas as Al Ṣuradain, the two Surad, desert birds differently described, — by some as "larger than sparrows" and variegated black and white (magpies?); by others as yellow and larger than doves.
γ, 3,1, yellow.
Al Naṣl, the Point, is Al Tizini's word designating this as marking the head of the Arrow; but Hyde cited Zujj al Nushshābah of similar meaning. The Borgian globe termed it Al Wazl, the Junction, indicating the spot where the arrow, bow, and hand of the Archer meet.
This star, with δ and ε and with β of the Telescope, was the sieu Ki, but in the worship of China the three were Feng Shï, the General of Wind.

δ, Double, 3 and 14.5, orange yellow and bluish.
Kaus Meridionalis, or Media, is Arabic and Latin for the Middle (of the Bow). It marked the junction of the two Ashādhā; and, with γ and ε, was the Akkadian Sin-nun‑tu, or Si-nu-nu‑tum, the Swallow.
The companion was 26ʺ away in 1896, at a position angle of 276°.4.

ε, Double, 2 and 14.3, orange and bluish,
is Kaus Australis, the Southern (part of the) Bow.
In Euphratean days it may have been Nibat Anu.
ε comes to the meridian on the 8th of August.
The companion is 32ʺ.5 away, at a position angle, in 1896, of 295°.
The comparison of the magnitudes of α, β, γ, δ, and ε in Sagittarius, each one being brighter than the preceding, goes far to show that Bayer was not guided in his star-lettering by any such rule of alphabetical arrangement in order of brilliancy as has been attributed to him.
ζ, Binary, 3.9 and 4.4.
The Latin Almagest of 1515 gives this as Ascella, i.e. Axilla, the Armpit of the figure, still its location on the maps.
The two components have the rapid orbital revolution of 18 1/2 years.
With σ, τ, and φ it formed a portion of the 18th manzil, Al Naʽām, or Al Naʽāïm al Ṣādirah, and the whole of that nakshatra; but the corresponding sieu included λ and μ, with φ as the determinant.

λ, 3.1, yellow.
Kaus Borealis, the Northern (part of the) Bow, was Al Tizini's Rāʽi al Naʽāïm, the Keeper of the Naʽams, the uncertainty as to the meaning of which has already been noticed; but Kazwini evidently understood by it Ostriches, for in his list it is, with the stars μ, Al Ṭhalimain, plainly meaning these desert birds.
With the same stars it may have been the Akkadian Anu-ni‑tum, said to have been associated with the great goddess Istar.
Near λ appeared in A.D. 386 a bright nova, the fourth on record; and 7° northeasterly the cluster 25 M. is visible to the naked eye.
μ1, Triple, 3.5, 9.5, and 1, and μ2, 5.8,
form a wide naked-eye double on the upper part of the bow, and are named in Akkadia and Arabia with the preceding star.
They mark the point of the winter solstice two thirds of the way southward towards, and in line with, the cluster NGC 6523, 8 M., visible to the naked eye, and with other noticeable clusters and nebulae close by. One of these, NGC 6603, 24 M. towards the northeast, is Secchi's Delle Caustiche, from its peculiar arrangement of curves, while the celebrated Trifid Nebula, NGC 6514, 20 M. lies not far off to the southwest. This was discovered in 1764, and so named from its three dark rifts; it is now specially noted from a suspected recent change in its position with regard to a star in one of these rifts. Spectroscopic observations of this object show considerable discordance in their results.
Brown says that the stars in the bow were the Persian Gau and the Sogdian and Khorasmian Yaugh, but by these nations were imagined as a Bull; the Copts knew them as Polis, a Foal.
ν1 and ν2, red stars of the 5th magnitude, 12ʹ apart, and both double, were ʽAin al Rāmī, the Archer's Eye. Ptolemy catalogued them as a nebulous double star, — νεφελοειδής καί διπλοῦς, — among the first to be so designated.
With ξ and ο they were the Chinese Kien Sing, a Flag-staff.
π, a 3d‑magnitude on the back of the head, was Al Tizini's Al Baldah, from the 19th manzil, which it marked; Al Achsasi considering it as Al Nāʼir, the Bright One, of that lunar station.
σ, 2.3.
This has been identified with Nunki of the Euphratean Tablet of the Thirty Stars, the Star of the Proclamation of the Sea, this Sea being the quarter occupied by Aquarius, Capricornus, Delphinus, Pisces, and Piscis Australis. It is the same space in the sky that Aratos designated as the Water; perhaps another proof of the Euphratean origin of much of Greek astronomy.
In India it marked the junction of the nakshatra Ashādhā with Abhijit.
It lies on the vane of the arrow at the Archer's hand.
σ, with ζ and π, may have been the Akkadian Gu-shi-rab‑ba, the Yoke of the Sea.
The 5th‑magnitude stars ψ1, χ1, and χ2 were the Chinese asterism Kow, the Dog.
ω, 4.8; A, 5; b, 4.7; and c, 4,
forming a small quadrangle on the hind quarter of the horse, were the τετράπλευρον of Ptolemy, which Bayer repeated in the Low Latin Terebellum, still often seen for these stars. The Standard Dictionary gives it thus, but mentions the components as ω, or a1, b and e.
The Chinese knew this little figure as Kow Kwo, the Dog's Country.

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