descension

descension is a   Noun

Definition:

[1] The act of going downward; descent; falling or sinking; declension; degradation. Oblique descension (Astron.), the degree or arc of the equator which descends, with a celestial object, below the horizon of an oblique sphere. -- Right descension, the degree or arc of the equator which descends below the horizon of a right sphere at the same time with the object. [Obs.]

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