The Color of the Sky

Frederic Zagury

Departmentof The History of Science, Harvard University, 02138 Cambridge, USA.

DOI: 10.4236/acs.2012.24045                

Abstract

The color of the sky in day-time and at twilight is studied by means of spectroscopy, which provides an unambiguous way to understand and quantify why a sky is blue, pink, or red. The colors a daylight sky can take primarily owe to Rayleigh extinction and ozone absorption. Spectra of the sky illuminated by the sun can generally be represented by a generic analytical expression which involves the Rayleigh function , ozone absorption, and, to a lesser extend, aerosol extinction. This study is based on a representative sample of spectra selected from a few hundred observations taken in different places, times, and dates, with a portable fiber spectrometer.

Keywords

Sky Color; Rayleigh Extinction; Ozone; Aerosols; Radiative Transfer; Spectral Analysis

Conflicts of Interest

The authors declare no conflicts of interest.

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