CrescentGeometry

moon-sighting v1.1.1

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moon-sighting / CrescentGeometry

Interface: CrescentGeometry

Defined in: types.ts:118

The five geometric quantities used by all major crescent visibility criteria. All values computed at best time (T_b) unless noted.

Properties

ARCL

ARCL: number

Defined in: types.ts:120

Arc of light: topocentric Sun-Moon angular separation (elongation), degrees

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ARCV

ARCV: number

Defined in: types.ts:125

Arc of vision: Moon airless altitude minus Sun airless altitude, degrees. Used as the primary visibility discriminant in both Yallop and Odeh.

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DAZ

DAZ: number

Defined in: types.ts:130

Relative azimuth: Sun azimuth minus Moon azimuth, normalized to [-180, 180], degrees. Positive = Moon north of Sun.

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lag

lag: number

Defined in: types.ts:137

Moonset minus sunset in minutes. Negative = Moon sets before Sun (no sighting possible).

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W

W: number

Defined in: types.ts:135

Topocentric crescent width in arc minutes. Used directly in Odeh's polynomial V expression.