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Aubé, M. (2007). Light pollution modeling and detection in a heterogeneous environment. Proceedings of Starlight 2007 conference. La Palma, Spain., .
Abstract: Few attempts have been made to measure aerosol optical depth (AOD) behaviour
during the night. One such method uses spectrally calibrated stars as reference targets
but the available number of stars is limited. This is especially true for urban sites where
artificial lighting hide most of these stars. In our research we attempt to provide an
alternate method one which exploits the artificial sky glow generated by light pollution.
To achieve that goal, we designed a new methodology which links a 3D light
pollution model with in situ light pollution spectral measurements obtained with our
detector called Spectrometer for aerosol night detection (SAND). The basic idea was to
adjust an AOD value into the model in order to fit the measured artificial sky brightness.
This method requires an accurate model that includes spatial heterogeneity in lighting
angular geometry, in lighting spectral dependence, in ground spectral reflectance and
in topography along with a detailed definition of the vertical atmospheric profile. This
model, named ILLUMINA, computes 1st and 2nd order molecular and aerosol scattering
as well as aerosol absorption. A correction for sub grid obstacles is also included.
These model features represent major improvements to previous light pollution models.
Therefore, new possibilities for light pollution studies will arise, many of which are of
particular interest to the astronomical community. In this paper we will present model
and detector features and some of the first results derived from ILLUMINA model. We
will also present our web based spatio-temporal Sky spectral luminance measurements
Aubé, M., Fortin, N., Turcotte, S., García, B., Mancilla, A., & Maya, J. (2014). Evaluation of the Sky Brightness at Two Argentinian Astronomical Sites. Publications of the Astronomical Society of the Pacific, , 000.
Abstract: Light pollution is a growing concern at many levels, especially for the astronomical community. Indeed, not only does artificial lighting veil celestial objects, it disturbs the measurement of many atmospheric phenomena. The sky brightness is one of the most relevant parameters for astronomical site selection. Our goal is to evaluate the sky brightness of two Argentinian observation sites: LEO ++ and El Leoncito. Both sites were preselected to host the Cherenkov Telescope Array. This project consists of an arrangement of many telescopes that can measure high-energy gamma ray emissions via their Cherenkov radiation produced when entering the earthâ€™s atmosphere. In this paper, we describe the measurement methods used to determine whether those sites are valuable or not. We compared our results with the sky radiance of different renowned astronomical sites (Kitt Peak, Arizona, and Mont-Mégantic, Québec, Canada). Among our results, we found that LEO ++ is a good site, however the presence of a low layer of local aerosol can introduce uncertainties in the measurements. Consequently, El Leoncito would be a better option for such an installation. This latter site shows very low sky brightness levels, which are optimal for low light detection.
Sánchez de Miguel, A., Kyba, C. C. M., Aubé, M., Zamorano, J., Cardiel, N., Tapia, C., et al. (2019). Colour remote sensing of the impact of artificial light at night (I): The potential of the International Space Station and other DSLR-based platforms. Remote Sensing of Environment, 224, 92–103.
Abstract: Sensors on remote sensing satellites have provided useful tools for evaluation of the environmental impacts of nighttime artificial light pollution. However, due to their panchromatic nature, the data available from these sensors (VIIRS/DNB and DMSP/OLS) has a limited capacity accurately to assess this impact. Moreover, in some cases, recorded variations can be misleading. Until new satellite platforms and sensors are available, only nighttime images taken with DSLR cameras from the International Space Station (ISS), airplanes, balloons or other such platforms can provide the required information. Here we describe a theoretical approach using colour-colour diagrams to analyse images taken by astronauts on the ISS to estimate spatial and temporal variation in the spectrum of artificial lighting emissions. We then evaluate how this information can be used to determine effects on some key environmental indices: photopic vision, the Melatonin Suppression Index, the Star Light Index, the Induced Photosynthesis Index, production of NO2-NO radicals, energy efficiency and CO2 emissions, and Correlated Colour Temperature. Finally, we use the city of Milan as a worked example of the approach.