%0 Journal Article
%A Bará, Salvador
%A Tilve, Victor
%A Nievas Rosillo, Mireia
%A Sánchez De Miguel, Alejandro
%A Zamorano Calvo, Jaime
%T Zernike power spectra of clear and cloudy light-polluted urban night skies
%D 2015
%@ 1559-128X
%U https://hdl.handle.net/20.500.14352/24105
%X The Zernike power spectra of the all-sky night brightness distributions of clear and cloudy nights are computed using a modal projection approach. The results obtained in the B, V, and R Johnson-Cousins' photometric bands during a one-year campaign of observations at a light-polluted urban site show that these spectra can be described by simple power laws with exponents close to -3 for clear nights and -2 for cloudy ones. The second-moment matrices of the Zernike coefficients show relevant correlations between modes. The multiplicative role of the cloud cover, that contributes to a significant increase of the brightness of the urban night sky in comparison with the values obtained on clear nights, is described in the Zernike space.
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