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) passing Portuguese slaving ship bound for Guinea, which replenished their supplies and escorted them to Santiago, Cape Verde. After resupply and repairs on Cape Verde (and taking on slaves to help make up for the missing crew), the ships set sail again, taking the route through the Azores islands, towards Lisbon. They were battered by storms and another wave of crew deaths on their final approach to Portugal. On September 16, 1504, the two remaining ships of the Fifth Armada, Afonso de Albuquerque's "Sant'Iago" and Fernão Martins de Almada's "São Cristóvão", in a terrible shape, hobbled into Lisbon harbor, with