Exploration
In the Pacific Ocean, Jorge de Menezes (c. 1498–?), discovered Papua New Guinea. García Jofre de Loaísa (1490–1526), discovered the Marshall Islands. Explorations of the Americas began with the initial discovery of America by Christopher Columbus (1451–1506), who led a Castilian (Spanish) expedition across the Atlantic, discovering America. After the discovery of America by Columbus, a number of important expeditions were sent out to explore the Western Hemisphere. This included Juan Ponce de León (1474–1521), who discovered and mapped the coast of Florida; Vasco Núñez de Balboa (c. 1475–1519), who was the first European to view the Pacific Ocean from American shores (after crossing the Isthmus of Panama) confirming that America was a separate continent from Asia; Aleixo Garcia (14?–1527), who explored the territories of present-day southern Brazil, Paraguay and Bolivia, crossing the Chaco and reaching the Andes (near Sucre).
New World
The Italian-born Spanish chronicler Peter Martyr d'Anghiera often shares credit with Vespucci for designating the Americas as a new world. Peter Martyr used the term "Orbe Novo" (literally, "New Globe", but often translated as "New World") in the title of his history of the discovery of the Americas as a whole, which began to appear in 1511 (cosmologically, "orbis" as used here refers to the whole hemisphere, while "mundus" refers to the land within it). Peter Martyr had been writing and circulating private letters commenting on Columbus's discoveries since 1493 and, from the start, doubted Columbus's claims to have reached East Asia ("the Indies"), and consequently came up with alternative names to refer to them. Only a few weeks after Columbus's return from his first voyage, Peter Martyr wrote letters referring to Columbus's discovered lands as the "western antipodes" ("antipodibus occiduis", letter of May 14, 1493), the "new hemisphere of the earth" ("novo terrarum hemisphaerio", September 13, 1493), and in a letter dated November 1, 1493, refers to Columbus as the "discoverer of the new globe" ("Colonus ille novi orbis repertor"). A year later (October 20, 1494), Peter Martyr again refers to the marvels of the New Globe ("Novo Orbe") and the "Western hemisphere."("ab occidente hemisphero").