SunCalc-Net

A .NET port of the SunCalc JS lib for calculating sun/moon positions and phases.

Getting Started

The best way to get started is to:

• Add a Nuget dependency to SunCalcNet.
• Use SunCalc and MoonCalc class methods.

Usage example

Get position of the sun (azimuth and altitude)

var date = new DateTime(2013, 3, 5, 0, 0, 0, DateTimeKind.Utc);
var lat = 50.5;
var lng = 30.5;

var sunPosition = SunCalc.GetSunPosition(date, lat, lng);

Assert.Equal(-2.5003175907168385, sunPosition.Azimuth, 15);
Assert.Equal(-0.7000406838781611, sunPosition.Altitude, 15);

Get position of the moon (azimuth, altitude, distance and parallactic angle)

var date = new DateTime(2013, 3, 5, 0, 0, 0, DateTimeKind.Utc);
var lat = 50.5;
var lng = 30.5;

var moonPosition = MoonCalc.GetMoonPosition(date, lat, lng);

Assert.Equal(-0.9783999522438226, moonPosition.Azimuth, 15);
Assert.Equal(0.0145514822438922, moonPosition.Altitude, 15);
Assert.Equal(364121.37256256194, moonPosition.Distance, 15);
Assert.Equal(-0.59832117604234014, moonPosition.ParallacticAngle, 15);

Get Sun phases

var date = new DateTime(2013, 3, 5, 0, 0, 0, DateTimeKind.Utc);
var lat = 50.5;
var lng = 30.5;

var sunPhases = SunCalc.GetSunPhases(date, lat, lng).ToList();

foreach (var sunPhase in sunPhases)
{
    ...
}

Get Moon Illumination

var date = new DateTime(2013, 3, 5, 0, 0, 0, DateTimeKind.Utc);

var moonIllum = MoonCalc.GetMoonIllumination(date);

Assert.Equal(0.4848068202456373, moonIllum.Fraction, 15);
Assert.Equal(0.7548368838538762, moonIllum.Phase, 15);
Assert.Equal(1.6732942678578346, moonIllum.Angle, 15);

About Suncalc.js

SunCalc is a tiny BSD-licensed JavaScript library for calculating sun position, sunlight phases (times for sunrise, sunset, dusk, etc.), moon position and lunar phase for the given location and time, created by Vladimir Agafonkin (@mourner) as a part of the SunCalc.net project.

Most calculations are based on the formulas given in the excellent Astronomy Answers articles about position of the sun and the planets. You can read about different twilight phases calculated by SunCalc in the Twilight article on Wikipedia.

Sun phases

Currently supported sun phases are:

Phase	Description
Sunrise	sunrise (top edge of the sun appears on the horizon)
SunriseEnd	sunrise ends (bottom edge of the sun touches the horizon)
GoldenHourEnd	morning golden hour (soft light, best time for photography) ends
SolarNoon	solar noon (sun is in the highest position)
GoldenHour	evening golden hour starts
SunsetStart	sunset starts (bottom edge of the sun touches the horizon)
Sunset	sunset (sun disappears below the horizon, evening civil twilight starts)
Dusk	dusk (evening nautical twilight starts)
NauticalDusk	nautical dusk (evening astronomical twilight starts)
Night	night starts (dark enough for astronomical observations)
Nadir	nadir (darkest moment of the night, sun is in the lowest position)
NightEnd	night ends (morning astronomical twilight starts)
NauticalDawn	nautical dawn (morning nautical twilight starts)
Dawn	dawn (morning nautical twilight ends, morning civil twilight starts)