RT Journal Article T1 Zernike analysis of all-sky night brightness maps A1 Bará, Salvador A1 Nievas Rosillo, Miguel A1 Sánchez de Miguel, Alejandro A1 Zamorano Calvo, Jaime AB All-sky night brightness maps (calibrated images of the night sky with hemispherical field-of-view (FOV) taken at standard photometric bands) provide useful data to assess the light pollution levels at any ground site. We show that these maps can be efficiently described and analyzed using Zernike circle polynomials. The relevant image information can be compressed into a low-dimensional coefficients vector, giving an analytical expression for the sky brightness and alleviating the effects of noise. Moreover, the Zernike expansions allow us to quantify in a straightforward way the average and zenithal sky brightness and its variation across the FOV, providing a convenient framework to study the time course of these magnitudes. We apply this framework to analyze the results of a one-year campaign of night sky brightness measurements made at the UCM observatory in Madrid. PB OSA pub. SN 1559-128X YR 2014 FD 2014-04-20 LK https://hdl.handle.net/20.500.14352/34297 UL https://hdl.handle.net/20.500.14352/34297 LA eng NO © 2014 Optical Society of America. This work was partially funded by the Xunta de Galicia, Programa de Consolidación e Estruturación de Unidades de Investigación Competitivas, grant CN 2012/156, the Spanish Ministry of Science and Innovation MICINN (AYA2012-30717, AYA2012- 31277, and FPA2010-22056-C06-06), the Spanish program of International Campus of Excellence Moncloa (CEI) and the Madrid Regional Government through the AstroMadrid Project (CAM S2009/ESP1496). A. Sánchez de Miguel was supported by an FPU grant from MICINN. This work was developed within the framework of the Spanish Network for Light Pollution Studies (Ministerio de Economía y Competitividad, Acción Complementaria AYA2011-15808-E) whose support is also acknowledged. NO Ministerio de Ciencia e Innovación (MICINN) NO Ministerio de Economía y Competitividad (MINECO) NO Comunidad de Madrid NO Xunta de Galicia NO Spanish program of International Campus of Excellence Moncloa (CEI) DS Docta Complutense RD 11 ago 2024