Arecibo Observatory 40th anniversary celebration

The National Astronomy and Ionosphere Center (NAIC), operated by Cornell University for the National Science Foundation, has its laboratory at Arecibo in Puerto Rico. The Observatory´s main instrument is a radio/radar telescope that utilizes a giant reflector antenna 1,000 feet in diameter, the largest in the world by a considerable margin. A 40th anniversary celebration of the 1963 inauguration of this Observatory was held at the site in Puerto Rico on 1 November 2003. About 135 invited guests enjoyed the nearly daylong ceremony. The author describes how he has been associated with the Observatory since its inception and notes some of the major discoveries and accomplishments radio scientists have made using the Arecibo Observatory over the last 40 years. The structure of the telescope is described. An account is given of the events taking place during the celebrations.