The Manila–Acapulco galleon trade finally began when Spanish navigators Alonso de Arellano and Andrés de Urdaneta discovered the eastward return route in 1565. Sailing as part of the expedition commanded by Miguel López de Legazpi to conquer the Philippines in 1564, Urdaneta was given the task of finding a return route. Reasoning that the trade winds of the Pacific might move in a gyre as the Atlantic winds did, they sailed north, going all the way to the 38th parallel north, off the east coast of Japan, before catching the westerlies that would take them back across the Pacific. He commanded a vessel which completed the eastward voyage in 129 days; this marked the opening of the Manila galleon trade.