Petrus Plancius was a Dutch astronomer and cartographer born in 1552. He is best known for his contributions to navigation and map-making during the Age of Exploration. Plancius played a significant role in the development of celestial navigation techniques, which were crucial for sailors at the time. In addition to his work in navigation, Plancius was also a prominent figure in the early Dutch East India Company. He created several important maps, including the first detailed map of the southern hemisphere, which helped explorers and traders better understand the world's geography. Plancius passed away in 1622.