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Enumeration: SunriseSunsetHorizon

Defined in: src/sdk/astro/AstroMath.ts:12

Types of horizons for calculating sunrise and sunset.

Enumeration Members​

AstronomicalTwilight​

AstronomicalTwilight: 3

Defined in: src/sdk/astro/AstroMath.ts:39

The horizon used to demarcate the boundary for the start and end of astronomical twilight. By convention, the sun crosses this horizon when its true (geometric) center is 18 degrees below the horizontal plane.

CivilTwilight​

CivilTwilight: 1

Defined in: src/sdk/astro/AstroMath.ts:27

The horizon used to demarcate the boundary for the start and end of civil twilight. By convention, the sun crosses this horizon when its true (geometric) center is 6 degrees below the horizontal plane.

Daylight​

Daylight: 0

Defined in: src/sdk/astro/AstroMath.ts:21

The horizon used to demarcate the boundary between daytime and nighttime. The sun crosses this horizon during the events colloquially known as "sunrise" and "sunset". By convention, the sun crosses this horizon when the top of the apparent solar disk crosses above or beneath the horizontal plane. Average values of 16 arcminutes and 34 arcminutes are taken for the sun's apparent angular radius and the atmospheric refraction at the horizontal plane, respectively. Therefore, the sun is considered to cross this horizon when its true (geometric) center is 50 arcminutes below the horizontal plane.

NauticalTwilight​

NauticalTwilight: 2

Defined in: src/sdk/astro/AstroMath.ts:33

The horizon used to demarcate the boundary for the start and end of nautical twilight. By convention, the sun crosses this horizon when its true (geometric) center is 12 degrees below the horizontal plane.