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
Peros Banhos in the geography of this atoll since the first maps were published in the mid-19th century. Île St. Brandon, which was covered with coconut trees when the first survey of this atoll was done, is now just a sandbank. On the other hand, in the western rim of Peros Banhos, the island north of Île Verte was only a small sandbank at the time of Commander Robert Moresby's Survey in 1837, but now it is a medium-sized island covered with vegetation. Peros Banhos was discovered in 1513 by Portuguese navigator Afonso de Albuquerque. The name of this atoll derives from