Cerro Pachón, an 8,800-foot (2,682-meter) mountain peak in northern Chile, has been selected as the site for the proposed Large Synoptic Survey Telescope (LSST).

Scheduled to see "first light" in 2012, the 8.4-meter telescope will survey the entire visible sky every three nights with its 3-billion-pixel digital camera. It will investigate the dark matter and dark energy thought to make up most of the universe, and track objects that move or change quickly, such as supernovae or asteroids.

"LSST will change the way we observe the universe by mapping the visible sky deeply, rapidly and continuously," said J. Anthony Tyson, professor of physics at UC Davis and director of the LSST project.

Four sites in Chile, Mexico and the Canary Islands were originally considered for the telescope. The finalists included Cerro Pachón and San Pedro Martir in Baja, Mexico. Cerro Pachón eventually was selected by the LSST Corporation board of directors, based on a recommendation from the Site Selection Committee.

Important factors included the number of clear nights per year, seasonal weather patterns, and the quality of images as seen through the local atmosphere. The chosen site also needed to have an existing observatory infrastructure and access to fiber optic links, to accommodate the anticipated 30 terabytes of data LSST will produce each night. Cerro Pachón is already home to the Gemini South 8-meter telescope and the 4.1-meter Southern Astrophysical Research telescope. LSST will be located on a peak on Cerro Pachón named El Peñón.

The LSST Corporation is a nonprofit 501(c) 3 Arizona corporation, with headquarters in Tucson. In addition to UC Davis, current members are the University of Arizona, Research Corporation, the National Optical Astronomy Observatory, the University of Washington, Brookhaven National Laboratory, Harvard-Smithsonian Center for Astrophysics, Johns Hopkins University, Kavli Institute for Particle Astrophysics and Cosmology at Stanford University, Las Cumbres Observatory Inc., Lawrence Livermore National Laboratory, Stanford Linear Accelerator Center, The Pennsylvania State University, University of Illinois at Urbana-Champaign, and the University of Pennsylvania.

The LSST research and development effort is funded in part by the National Science Foundation. Additional funding comes from private donations, in-kind support at Department of Energy laboratories and other institutional members.