University of Arizona's Steward Observatory Richard F. Caris Mirror Laboratory, Tucson

About University of Arizona's Steward Observatory Richard F. Caris Mirror Laboratory

The Richard F. Caris Mirror Laboratory at the University of Arizona in Tucson offers 90-minute guided tours of one of the world's most advanced facilities for creating astronomical mirrors. Visitors begin at the historic Steward Observatory, established in 1917, where an introductory presentation takes place in the building's iconic white-brick dome. The tour then proceeds to the Mirror Lab, located beneath the university's football stadium, where guests observe the engineering, optical science, and precision manufacturing processes involved in creating massive telescope mirrors. Each mirror measures 8.4 meters in diameter and will eventually become part of the Giant Magellan Telescope, a next-generation instrument composed of seven such segments forming a 25-meter primary mirror. On the tour, visitors watch glassmaking, precision polishing, and optical testing procedures firsthand. The experience involves walking, climbing, and descending through the facility. Tours operate Monday through Friday, with varying start times. The attraction charges admission, with prices published online.