Artificial Light at Night (ALAN) Research Literature Database -- Query Results

Garstang, R. H. (2000). Limiting visual magnitude and night sky brightness. Memorie della Società Astronomia Italiana, 71. Abstract: We review the theory of visual thresholds and applications to the limiting magnitude of a telescope and of the eyes, based on Schaefers's model with minor improvements. We apply out formulation to the Yerkes Observatory refractor and to naked eye observations at Mount Wilson Observatory. We reanalyze Bowen's telescopic observations at Mount Wilson by his approximate method and by our more elaborate theory. An extension of his method leads to a determination of the night sky brightness of the visual activity of the observer is assumed to be average. Our more elaborate method allows a determination of the sky brightness, the visual acuity of the observer, and the average seeing during the observations. Keywords: Skyglow http://alandb.darksky.org/show.php?record=2623
Garstang, R. H. (2000). Light Pollution at Mount Wilson: The Effects of Population Growth and Air Pollution. Memorie della Società Astronomia Italiana, 71(1). Abstract: This is the first part of a study of the historical growth of light pollution at Mount Wilson Observatory. The night sky brightness at Mount Wilson due to light pollution from Los Angeles basin was calculated for the years 1910 to 1990, neglecting changes in lighting technology, and without any air pollution ('smog'). The very large effect of population growth is shown. We made a simple extension of our night sky brightness program to include a layer of smog. Two possibilities of constant density and finite thickness. The ground level density is determined by the visibility. We assume a smog layer whose density increases from zero in 1920 to appropriate values for the years from 1950. We added this layer to out model and repeated the Mount Wilson calculations. An average smog layer reduces the visual brightness at the present time by about 6 percent. Keywords: Skyglow http://alandb.darksky.org/show.php?record=2544

Abstract: We review the theory of visual thresholds and applications to the limiting magnitude of a telescope and of the eyes, based on Schaefers's model with minor improvements. We apply out formulation to the Yerkes Observatory refractor and to naked eye observations at Mount Wilson Observatory. We reanalyze Bowen's telescopic observations at Mount Wilson by his approximate method and by our more elaborate theory. An extension of his method leads to a determination of the night sky brightness of the visual activity of the observer is assumed to be average. Our more elaborate method allows a determination of the sky brightness, the visual acuity of the observer, and the average seeing during the observations.

Abstract: This is the first part of a study of the historical growth of light pollution at Mount Wilson Observatory. The night sky brightness at Mount Wilson due to light pollution from Los Angeles basin was calculated for the years 1910 to 1990, neglecting changes in lighting technology, and without any air pollution ('smog'). The very large effect of population growth is shown. We made a simple extension of our night sky brightness program to include a layer of smog. Two possibilities of constant density and finite thickness. The ground level density is determined by the visibility. We assume a smog layer whose density increases from zero in 1920 to appropriate values for the years from 1950. We added this layer to out model and repeated the Mount Wilson calculations. An average smog layer reduces the visual brightness at the present time by about 6 percent.

Keywords: Skyglow

http://alandb.darksky.org/show.php?record=2544