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David

Darling

Cerro Tololo Inter-American Observatory

Cerro Tololo Inter-American Observatory

The Cerro Tololo Inter-American Observatory (CTIO) is a complex of astronomical telescopes and instruments located 70 km east of La Serena, Chile, at an altitude of about 2,200 m on Cerro Tololo mountain. Founded in 1963 and part of the U.S. National Optical Astronomy Observatories, its main instrument is the 4-m Blanco Telescope, opened in 1976, that is the southern twin of the 4-m instrument at Kitt Peak National Observatory. On a peak 10 km to the southeast is the 8-m Gemini South telescope.