Though the peoples of Asia and Oceania have travelled the Pacific Ocean since prehistoric times, the eastern Pacific was first sighted by Europeans in the early 16th century when Spanish explorer Vasco Nunez de Balboa crossed the Isthmus of Panama in 1513 and discovered the great"southern sea" which he named Mar del Sur.The ocean's current name was coined by Portuguese explorer Ferdinand Magellan during the Spanish circumnavigation of the world in 1521,as he encountered favourable winds on reaching the ocean. He called it Mar Pacifico, which in both Portuguese and Spanish means "peaceful sea