Foucault Pendulum

Foucault Pendulum

One of SCI's most iconic and beloved experiences, the Foucault Pendulum is a 235-pound, 17-inch brass ball demonstrating the rotation of the earth, which previously hung for more than 30 years in the Science Center of Iowa's former location in Greenwood-Ashworth Park.

The pendulum was first devised in 1851 by the French physicist Leon Foucault, who suspended a large iron ball and set it swinging along a north-south line. Spectators saw it slowly turn in a clockwise direction. They were in fact observing the counter-clockwise motion of the Earth under the invariable swing of the pendulum.

SCI's pendulum is suspended from the ceiling by a 41-foot-long cable where a circular electro-magnet keeps it swinging indefinitely in a 7.5-foot arc and knocking over two of the 427 steel pegs surrounding the frame of the pendulum every five minutes.

Located on SCI’s Main Level near the NE corner of the building.