Zenit körüli ív - Circumzenith arc
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Felső érintőív - Upper tangent arc
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[...] This year was the first day of Pentecost on the nones of June; and on the Tuesday following were seen four circles at mid-day about the sun, of a white hue, each described under the other as if they were measured. All that saw it wondered; for they never remembered such before. (The Peterborough Chronicle, 1104 A.D.)
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