Planetarium and Immersion Room “El PENDULO”

 

The most significant and fascinating Foucault pendulum in the world, in terms of its importance in the history of science, is located at the Panthéon in Paris, France, where Léon Foucault installed the first large-scale pendulum.

 

In Mexico, there are currently six Foucault pendulums:

 

• In the Metropolitan Cathedral in Mexico City

• At the Center for Innovation and Application of Science and Technology (CIACYT) in San Luis Potosí

• At the Explora Science Museum in Leon, Guanajuato

• At the Center for Science in Sinaloa

• At the Library of the Universidad Autónoma Metropolitana (UAM), Azcapotzalco campus in Mexico City

• And of course, the Foucault Pendulum located in the Manuel Gomez Morin Educational and Cultural Center in Querétaro.

 

We invite you to visit this remarkable mechanism, which elegantly demonstrates the Earth’s rotation.

 

Design and Construction

​

In 2002, the idea of designing, building, and installing a Foucault pendulum in the capital of the state of Queretaro was conceived. The Center for Applied Physics and Advanced Technology (CFATA) of the National Autonomous University of Mexico (UNAM), under the guidance of Dr. Miguel de Icaza Herrera and Dr. Víctor Manuel Castaño Meneses, was responsible for its design and direction. The construction was carried out by the Center for Advanced Engineering A.C. (CIATEQ), with the support of the Science and Technology Council of Queretaro (CONCYTEQ).

 

A dedicated building was constructed to house the pendulum, featuring a dome 36 meters in diameter and 28 meters high.

 

Technical Specifications

 

The Foucault Pendulum of Queretaro is suspended by a braided steel cable measuring 28 meters in length, including the bob. The bronze bob weighs 280 kilograms and has a diameter of 64 centimeters, making it the largest pendulum sphere in Mexico. It rotates clockwise, completing one full revolution every 67 hours, which means it advances 5.3 degrees per hour.

 

Its movement is influenced by air friction, Coriolis forces, cable tension, oscillations, and even minor seismic activity—whether natural or human-made. To maintain its motion, it is equipped with a hydraulic control system that provides periodic impulses, ensuring the pendulum continues swinging until it completes a full rotation.

 

Inauguration and Legacy

 

In February 2005, the Foucault pendulum in Queretaro began operating, and it continues to impress visitors to this day with its scientific beauty and precision.