1. The obvious next step is for light level studies to be conducted in different parts of the world using the Sky Quality Meter (SQM) to establish what principles are universal and which are relative to latitude. Also the impact of climate will be further clarified with the study in warmer countries closer to the equator.

If you require more details or need support on conducting your own SQM study then please contact us.

2. Computer modeling is required to establish the interaction of moonlight and twilight on light level reading so as to remove the variable of moonlight when trying to calculate Fajr. With the modelling of the depression angle of the sun against the resulting light level, it will become possible to create a function which can be applied to any location.

3. A number of luminance scales exist and used for different purposes. The mapping of the magnitudes per square arcsecond (MPAS) against these may expand the understanding of the light conditions associated with Subh al-Sadiq (dawn):

  • Candela per square meter - used by lighting engineers
  • Naked Eye Limiting Magnitude (NELM) - used by astronomers to define the darkest star they can see (e.g. 6th magnitude sky)
  • Natural Sky Units (NSU) - Comparison to assumed natural radiance