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).
Tunnel Through the Deeps
In an alternative history, the United States lost the American Revolutionary War and George Washington was executed for treason. Thus, America in 1973 is still under the control of the British Empire. The divergence point between this world and our own occurred far earlier, however, when the Moors won the battle of Navas de Tolosa on the Iberian peninsula, on July 16, 1212. Thus it was that Spain was unable to become unified, owing to the survival of an Islamic presence in its territory, and therefore could not finance the expedition of Christopher Columbus in 1492. Instead, it was John Cabot who discovered America, just a few years later.