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Cerro Tololo Inter-American Observatory

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Management, Operations, and Associated Projects for the National Optical Astronomy Observatory  (AURA/National Optical Astronomy Observatories)

Research Focus & Anticipated Benefits

Cerro Tololo Inter-American Observatory was established in the 1960s to take advantage of the high altitude and low humidity of peaks in the southern Atacama Desert of Chile, ideal for night-time observing. Its accessibility to U.S. scientists greatly expanded their ability to study astronomical objects visible only from the southern hemisphere, including the Magellanic Clouds, the brightest globular clusters, and the clusters and nebulae-rich Carina-Centaurus region of the Milky Way.

CTIO operates the 4-meter Blanco telescope on Cerro Tololo and a newer 4.1-meter Southern Astrophysical Research (SOAR) Telescope on nearby Cerro Pachon. Several smaller telescopes on Cerro Tololo operated by other organizations are also available to U.S. astronomers.

Developed and operated in collaboration with South American partners, Cerro Tololo Inter-American Observatory is part of the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy under a cooperative agreement with the National Science Foundation. One of the six international stations of the National Solar Observatory's Global Oscillation Network Group, which studies the interior of the sun, is co-located on the CTIO site.

Education & Outreach

The facilities of the National Optical Astronomy Observatory offer numerous education and outreach opportunities.  Cerro Tololo Inter-American Observatory participates in NOAO programs to provide hands-on education and training for all levels of students and teachers as well as bilingual tours and informational materials for visitors. For higher education students, the observatory offers the opportunity to study and train with professional mentors--through NSF-sponsored Research Experiences for Undergraduates and graduate student and postdoctoral research program.

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  • Cerro Tololo telescopes