true2000 function

({double anomaly, double lon}) true2000(
  1. double t
)

True geometric longitude referenced to equinox J2000.

Implementation

({double lon, double anomaly}) true2000(double t) {
  final sun = trueSun(t);
  return (
    lon: sun.lon - toRad(0.01397) * t * 100,
    anomaly: sun.anomaly,
  );
}