Diego Ram%C3%ADrez de Arellano

Diego Ramrez de Arellano was a Spanish sailor and cosmographer. He achieved fame for piloting the Garcia de Nodal expedition to the region of the Strait of Magellan. The expedition discovered the Diego Ramrez Islands, the most southerly point visited by Europeans until the discovery of the South Sandwich Islands by Captain James Cook in 1775.

Diego Ramrez de Arellano was born in Xtiva in Valencia around 1580. He was appointed the main pilot in the 1618 expedition led by the brothers Bartolom and Gonzalo Garca del Nodal to explore the region of the Straits of Magellan. The expedition consisted of two caravels. Ramrez was charged with astronomical observations and with preparing charts with the help of Juan Manso and seven other pilots, four in each caravel. They had modern astrolabes that could measure angles of five minutes of arc, giving much more accuracy than older instruments.

Source: Wikipedia