La Silla Observatory

La Silla Observatory is an astronomical observatory in Chile with three telescopes built and operated by the European Southern Observatory (ESO). Several other telescopes are located at the site and are partly maintained by ESO. The observatory is one of the largest in the Southern Hemisphere and was the first in Chile to be used by ESO. The La Silla telescopes and instruments are located 150 km northeast of La Serena at the outskirts of the Chilean Atacama Desert, one of the driest and most remote areas of the world. Like other observatories in this geographical area, La Silla is located far from sources of light pollution and, like the Paranal Observatory, home to the Very Large Telescope, it has one of the darkest night skies on the Earth. Following the decision in 1963 to approve Chile as the site for the ESO observatory, scouting parties were sent to various locations to assess their suitability. The site that was decided upon was La Silla in the southern part of the Atacama desert, 600 km north of Santiago de Chile and at an altitude of 2400 metres. Besides being government property, it had the added benefits of being in a dry, flat and easily accessible area, yet isolated and remote from any artificial light and dust sources. Originally named the Cinchado, it was renamed La Silla ("the saddle" in Spanish) after its saddle-like shape. On October 30, 1964, the contracts were signed and an area of was purchased the following year. During 1965, temporary facilities were erected with living quarters, a workshop and storage area. The dedication ceremony of the road to the summit took place in March 1966, two months after completion of the road. On 25 March 1969, the ESO site at La Silla was finally formally inaugurated by President Eduardo Frei Montalva. With a permanent base of dormitories, workshops, hotels and several functioning telescopes, the observatory was fully operational. The ESO 1.5-metre and ESO 1-metre telescopes had been erected in the late 1960s, and were joined in 1968 by the Gran Prismo Objectif telescope, which had previously been used in South Africa.