Sky Brightness

Martin Elsässer, 2018

I tried to implement a very simple 2D model of scattered light in our atmosphere after sunset to judge the brightness of the sky through which we would try to see a thin lunar crescent.

sky brightness, solar elevation
This diagramm shows the brightness of the sky for various values of sun elevation (below the horizon) and lunar elongation.


Limitations of the underlying model


  1. Extend the modell to 3D, to get a map of sky brightness above the horizon.
  2. Actually measure the change of brightness of the twilight sky on a clear evening/morning.
  3. Search for better treatments of this topic in the literature. All of this will have been done before and better, most surely.