Earth's rotation Foucault in 1851, which consisted of a lead-filled brass sphere suspended from the top of the Panthéon in Paris. Because of the Earth's rotation under the swinging pendulum, the pendulum's plane of oscillation appears to rotate at a rate depending on latitude. At the latitude of Paris the predicted and observed shift was about clockwise per hour. Foucault pendulums now swing in museums around the world. Earth's rotation period relative to the Sun (solar noon to solar noon) is its "true solar day" or "apparent solar day". It depends on the Earth's orbital motion and is thus affected by changes
Griffith Observatory the Foucault pendulum, which was designed to demonstrate the rotation of the Earth. The exhibits also included a 12-inch (305mm) Zeiss refracting telescope in the east dome, a triple-beam coelostat (solar telescope) in the west dome, and a thirty-eight foot relief model of the moon's north polar region. Col. Griffith requested that the observatory include a display on evolution which was accomplished with the Cosmochron exhibit which included a narration from Caltech Professor Chester Stock and an accompanying slide show. The evolution exhibit existed from 1937 to the mid-1960s. Also included in the original design was a planetarium under the