Ascension Island a staging point by the British military during the Falklands War. Ascension Island hosts one of four ground antennas (others are on Kwajalein Island, Diego Garcia, and Cape Canaveral) that assist in the operation of the Global Positioning System (GPS) navigational system. NASA operates a Meter Class Autonomous Telescope (MCAT) on Ascension Island for tracking orbital debris, which is potentially hazardous to operating spacecraft and astronauts, at a facility called the John Africano NASA/AFRL Orbital Debris Observatory. In 1501, the Portuguese navigator Afonso de Albuquerque sighted the island on Ascension Day (which fell on 21 May that year) and named
NRP Afonso de Albuquerque (1934) and Daman and Diu by force. At the time, "Afonso de Albuquerque" was based in Goa as the leading naval unit of the Portuguese India Naval Command, with Captain Cunha Aragão as her commander. Early on the morning of 18 December 1961 "Afonso de Albuquerque" received information that the Indian Armed Forces had launched Operation Vijay. Her crew went to battle stations. As the land communication infrastructure was bombed and destroyed by the Indian Air Force, "Afonso de Albuquerque" received the responsibility to maintain radio communications between Goa and Lisbon. At 0900, "Afonso de Albuquerque" sighted three Indian Navy ships,