Determines if a location on earth is illuminated by the sun.

Namespace: Zeptomoby.OrbitTools.Track
Assembly: Zeptomoby.OrbitTools.Track (in Zeptomoby.OrbitTools.Track.dll) Version: (


public static bool InSunlight(
	this Site site,
	DateTime utc,
	double degTwilight
Visual Basic
<ExtensionAttribute> _
Public Shared Function InSunlight ( _
	site As Site, _
	utc As DateTime, _
	degTwilight As Double _
) As Boolean
Visual C++
static bool InSunlight(
	Site^ site, 
	DateTime utc, 
	double degTwilight


Type: Site
The earth location.
Type: System..::..DateTime
Time of calculation (UTC).
Type: System..::..Double
The elevation angle of the sun when twilight begins, in degrees.

Return Value

Returns 'true' if the site is illuminated by sunlight. The site is assumed to be in sunlight for all sun elevation angles that exceed the twilight angle.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type Site. When you use instance method syntax to call this method, omit the first parameter. For more information, see or .


Some common twilight angles, in degrees: -6.0 Civil Twilight -12.0 Nautical Twilight -18.0 Astronomical Twilight

See Also