solar-calculator/src/set.js

Equations for computing the position of the Sun.

import noon from "./noon";
import riseHourAngle from "./riseHourAngle";

export default function(date, latitude, longitude) {
  date = noon(date, longitude);
  return new Date(+date - riseHourAngle(date, latitude) * 4 * 1000 * 60);
}