Fernando de Noronha (fərnänˈdŏ dĭ nŏrôˈnyə) [key], group of 21 islands, c.10 sq mi (26 sq km), in the Atlantic Ocean, c.225 mi (360 km) off the northeast coast of Brazil. A federal territory of Brazil from 1942 to 1988, when it was reannexed to the state of Pernambuco, it is administered as a state district and is the site of a national maritime park. The islands have been the site of a military base and a penal colony. The main resources on the islands are guano and salt deposits. Tourism is the mainstay of the economy. The islands, discovered in 1503, were the first hereditary captaincy granted in Brazil by the Portuguese crown. A U.S. missile-tracking base was there from 1957 to 1962.