hour-angle ( timestamp latitude -- degrees )

Vocabulary

calendar.private

Inputs

timestamp	an object
latitude	an object

Outputs

degrees

an object

Definition

USING: math math.functions ;

IN: calendar.private

:: hour-angle ( timestamp latitude -- degrees )
    timestamp declination :> decl latitude deg>rad :> lat 90.833
    deg>rad cos lat cos decl cos * / lat tan decl tan * -
    acos rad>deg ;