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
5th Portuguese India Armada (Albuquerque, 1503) their handful of crew and leaking hulls. They were well received. Albuquerque is said to have presented some splendid specimens of Persian horses acquired in the Indian markets to the king. By and large, the 5th Armada was a disaster. Of the ten ships that set out, only two were known to have returned on time (Afonso de Albuquerque, Fernão Martins de Almada). Two were lost around the Cape on the outgoing voyage ("Catharina Dias" and the ship of Vaz da Veiga), two ships were lost on the return (F. Albuquerque, Coelho) and a third (the ship captained by Ataíde)