SITE VISIT UPDATE
L-R: Chuck Claver, Victor Krabbendam, Don Sweeney and Steve Kahn.
In May 2006 LSST Corp selected 2,682-meter (8,800-foot) Cerro Pachón in northern Chile for the site of the LSST Observatory. This selection followed two years of in-depth testing and analysis of the atmospheric conditions and utility for hosting the LSST. From numerous worldwide sites candidates, the project team narrowed the selection to four finalists, sites in Chile, Mexico and the Canary Islands, and then settled on Cerro Pachón as the best choice. With the selection made, work has continued to characterize the site and 2008 will see the start of rough excavation. 2008 will also see the selection of an architecture & engineering firm.
An ongoing data-taking and evaluation campaign continues. Instrumentation on the site includes two all-sky cameras (infrared and visible), a differential image monitor (DMM). Future newsletter issues will highlight the instruments and results of the analyses.
Cerro Pachón as seen from Cerro Tololo.
Structural analysis of the telescope also continues. One aspect that must be taken into account is the impact of seismic events at the site. Chilean observatories have experienced earthquakes of over 7.0 magnitude on the Richter Scale and are frequently jostled by smaller magnitude tremors. Observatories in Chile, as elsewhere, have long-established systems for design and operations in an earthquake zone. In December, these observatories hosted an earthquake conference to address design and operational needs due to earthquakes.
LSST modal analysis has been developed in steps and now includes the concrete pier and rock base. The results led to a design of a wide pier with stepped thickness to provide stiff support for the telescope. The detailed analysis of the telescope top end showed a factor of 10 safety margin for buckling under maximum operations and earthquake transverse and vertical loading.
For more information, contact Victor Krabbendam, Telescope and Site Manager.
LSST E-News is a free email publication of the Large Synoptic Survey Telescope Project. It is for informational purposes only, and the information is subject to change without notice.
Subscribe/Unsubscribe
Copyright © 2008 LSST Corp., Tucson, AZ • www.lsst.org