Two-index model for characterizing site-specific night sky brightness patterns

TL;DR

This paper introduces a two-parameter analytical model to efficiently and accurately characterize the all-sky brightness distribution caused by artificial light sources, simplifying computations in light pollution studies.

Contribution

The work presents a novel analytic formulation that reduces computational complexity by using only two parameters to describe sky brightness patterns from artificial lights.

Findings

Efficient calculation of all-sky radiance distributions.

Accurate modeling with fewer parameters.

Potential for new light pollution applications.

Abstract

Determining the all-sky radiance distribution produced by artificial light sources is a computationally demanding task that generally requires an intensive calculation load. We develop in this work an analytic formulation that provides the all-sky radiance distribution produced by an artificial light source as an explicit and analytic function of the observation direction, depending on two single parameters that characterize the overall effects of the atmosphere. One of these parameters is related to the effective attenuation of the light beams, whereas the other accounts for the overall asymmetry of the combined scattering processes in molecules and aerosols. By means of this formulation a wide range of all-sky radiance distributions can be efficiently and accurately calculated in a short time. This substantial reduction in the number of required parameters, in comparison with other currently used approaches, is expected to facilitate the development of new applications in the field of light pollution research.