The 'Zodiacal Light', 20 February 1876.
© Science Museum / Science & Society Picture Library
Colour print by Etienne Leopold Trouvelot (1827-1895), one of a set of 15, made by him whilst in the United States between 1872 and 1881. The lithographs are based on the French artist's observations from various American observatories. Titled 'The Zodiacal Light', the print shows the faint and diffuse wedge of light that can seen in dark skies on moonles nights for several hours after sunset or before sunrise during the spring and autumn. More easily seen in the tropics, the phenomenon is caused by scattering of sunlight off interplanetary dust in the ecliptic plane, the annual path of the Sun acros the sky.