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
João Afonso de Albuquerque I of Castile, who is suspected of having him poisoned in 1354. His father, Afonso Sanches, was the firstborn and favorite son of King Dinis I of Portugal who had him out of wedlock with Aldonza Rodrigues Telha. Teresa Martins de Meneses, his mother, was the daughter of João Afonso Telo, the first count of Barcelos, and of Teresa Sánchez, an illegitimate daughter of Sancho IV the Brave, king of Castile and León. Teresa survived her husband by almost twenty years. João Afonso de Albuquerque was raised in Lisbon at the house of João Simão de Urrô who in 1314