Cerro Tololo Observatory

The Cerro Tololo Inter-American Observatory (CTIO) is an astronomical observatory located on Cerro Tololo in the Coquimbo Region of northern Chile, with additional facilities located on Cerro Pachón about to the southeast. It is approximately east of La Serena, where support facilities are located. The site was identified by a team of scientists from Chile and the United States in 1959, and it was selected in 1962. Construction began in 1963 and regular astronomical observations commenced in 1965. Construction of large buildings on Cerro Tololo ended with the completion of the Víctor Blanco Telescope in 1974, but smaller facilities have been built since then. Cerro Pachón is still under development, with two large telescopes (Gemini South and SOAR) inaugurated since 2000, and one in the early stages of construction (the Vera C. Rubin Observatory)

The principal telescopes at CTIO are the 4 m Víctor M. Blanco Telescope, named after Puerto Rican astronomer Víctor Manuel Blanco, and the 4.1 m Southern Astrophysical Research Telescope, which is situated on Cerro Pachón. Other telescopes on Cerro Tololo include the 1.5 m, 1.3 m, 1.0 m, and 0.9 m telescopes operated by the SMARTS consortium. CTIO also hosts other research projects, such as PROMPT, WHAM, and LCOGTN, providing a platform for access to the southern hemisphere for U.S. and worldwide scientific research.

Organization

CTIO is one of two observatories managed by NOIRLab, the other being Kitt Peak National Observatory (KPNO) near Tucson, Arizona. NOIRLab is operated by the Association of Universities for Research in Astronomy (AURA), which owns the property around the two peaks in Chile and at the headquarters in La Serena, Chile. AURA also operates the Space Telescope Science Institute and the Gemini Observatory. The Gemini South Telescope located on Cerro Pachón is managed by AURA separately from CTIO for an international consortium. The National Science Foundation (NSF) is the funding agency for NOIRLab.

The Small and Medium Research Telescope System (SMARTS) is a consortium formed in 2001 after NOAO, the predecessor to NOIRLab, announced it would no longer support anything smaller than two meters at CTIO. The member institutions of SMARTS now fund and manage observing time on four telescopes that fit that definition. Access has also been purchased by individual scientists. SMARTS contracts with NOIRLab to maintain the telescopes it controls at CTIO, and NOIRLab retains the right to 25% of the observing time, and Chilean scientists retain 10%. SMARTS began managing telescopes in 2003.

CTIOPI is the Cerro Tololo Interamerican Observatory Parallax Investigation. It began in 1999 and uses two telescopes at Cerro Tololo, the SMARTS 1.5 m reflector and the SMARTS 0.9 m reflector. The purpose of CTIOPI is to discover nearby red, white, and brown dwarfs that lurk unidentified in the solar neighborhood. The goal is to discover 300 new southern star systems within 25 parsecs by determining trigonometric parallaxes accurate to 3 milliarcseconds.

Telescopes

* The Víctor M. Blanco Telescope (Blanco 4m) was completed in 1974 and is very similar to the Nicholas U. Mayall Telescope that was completed at KPNO in 1973. Testing of the telescope and instruments lasted until the beginning of 1976 when science operations began. The Blanco 4m is the only telescope on Cerro Tololo managed directly by NOIRLab.
* The Southern Astrophysical Research Telescope (SOAR) is an optical and near-infrared telescope located on Cerro Pachón. It was dedicated in 2004 and is managed by NOIRLab for an international consortium of which NOIRLab is a partner.

SMARTS telescopes

* The SMARTS Telescope is a Cassegrain reflector on an equatorial mount. Regular observations began in 1968.
* The SMARTS Telescope is a Cassegrain reflector on an equatorial mount. It was built by M3 Engineering and Technology Corporation and used for the 2-micron All-Sky Survey (2MASS). It began operating in 1998 and was given to CTIO in 2001 after the survey was completed.
* The SMARTS Yale Telescope is a closed-tube Cassegrain reflector built by Boller and Chivens. It was first installed in 1965 at the Bethany Observing Station of the Yale University Observatory. It was moved to CTIO in 1974. From 1998 to 2002, it was used by the Yale University–AURA–University of Lisbon–Ohio State University (YALO) consortium with a custom-built sensor. In 2004 it was integrated into SMARTS.
* The SMARTS Telescope is a closed-tube Cassegrain reflector. It was installed at CTIO in 1966.

Tenant telescopes

* The Southeastern Association for Research in Astronomy (SARA) South Telescope is a reflecting telescope built by Boller and Chivens. Installed in 1968 for the International Planetary Patrol Program, it was owned and operated by Lowell Observatory. At some point control shift to CTIO, which lasted until 1996, after which Lowell used the telescope intermittently. It was refurbished by SARA and put back into use in 2010. Observing time is shared between the members of the SARA consortium.
* The Curtis-Schmidt Telescope is a Schmidt camera that was installed at CTIO in 1966. Previously, it was located at the University of Michigan's Portage Lake Observatory. It is currently used for the Michigan Orbital DEbris Survey Telescope (MODEST) project, which is part of NASA's program to detect and catalog orbital debris. Two-thirds of observing time was at the discretion of NOAO prior to 2001. From 1989 to 1995 it was used in part by the Calán/Tololo Survey.
* The Wisconsin H-Alpha Mapper (WHAM) is a custom-built telescope used to study the warm ionized medium. In 2009, it was moved to CTIO from KPNO, where it operated from 1996 to 2008.
* A reflecting telescope built by Officina Stellare of Italy was installed in 2010 as part of the Chilean Automatic Supernova Search