Mount Lemmon Observatory

Mount Lemmon Observatory, in the Santa Catalina Mountains northeast of Tucson, is a cluster of independently managed telescopes used for research and public astronomy under the University of Arizona’s Steward Observatory. First developed in 1954 as Mount Lemmon Air Force Station, the site was transferred in 1970 and converted from Cold War radar work to infrared astronomy, though a radar tower remained active until 2003. Its major instruments include two 1.52-meter telescopes, one used in the Mount Lemmon Survey for near-Earth objects. Smaller telescopes support asteroid follow-up, near-infrared observing, exoplanet photometry, student programs, remote imaging, and public education.

Summerhaven, Arizona · United States