Mount Laguna Observatory
Astronomical observatory

Mount Laguna Observatory (MLO) is an astronomical observatory owned and operated by San Diego State University (SDSU). MLO is located approximately 75 kilometers (47 mi) east of downtown San Diego, California, on the eastern edge of Cleveland National Forest, in the Laguna Mountains on the SDSU Astronomy Campus near the hamlet of Mount Laguna.
MLO was dedicated on June 19, 1968, seven years after SDSU's Department of Astronomy became an independent academic department of SDSU's College of Sciences. The dedication took place during the 1968 summer meeting of the Astronomical Society of the Pacific. The telescope was operated in partnership with the University of Illinois at Urbana-Champaign (UIUC) until 2000. Currently, SDSU is working with the University of Kansas (KU) and the University of North Carolina at Chapel Hill on various projects.
Telescopes
The 1.06 m (42 in) MLO 40-inch telescope is a Cassegrain reflector built by Astro Mechanics in 1966. It was originally fitted with a 1.02 m (40 in) primary mirror which has since been replaced. It is known informally as the Illinois telescope because it was located at UIUC's Prairie Observatory until 1981.
The 0.6 m (24 in) Clifford Smith 24-inch telescope is a Cassegrain reflector.
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This entry incorporates text from “Mount Laguna Observatory” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.