“Awake! for Morning in the Bowl of Night / Has flung the Stone that puts the Stars to Flight: / And Lo! the Hunter of the East has caught / The Sultan's Turret in a Noose of Light.”
The hint
The Hunter of the East caught it in his noose, and it came in tail first.
The cipher
KAERBYAD
— Omar Khayyám · The Rubáiyát, I · tr. Edward FitzGerald, 1859
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