Which development most aided explorers in their ability to sail the oceans discover New World during Age of Discovery?

The astrolabe is a navigational instrument that was used to measure the altitude of celestial bodies above the horizon. This allowed explorers to determine their latitude, which was essential for long-distance travel. Prior to the astrolabe, explorers had to rely on less accurate methods of determining their latitude, such as the quadrant or the cross-staff. The astrolabe was a major breakthrough in navigation, and it played a key role in the Age of Discovery.

By enabling sailors to chart their position with improved accuracy, the astrolabe helped explorers like Christopher Columbus, Vasco da Gama, and Ferdinand Magellan navigate vast oceans, leading to groundbreaking geographical discoveries like the Americas, India, and the circumnavigation of the globe. This instrument revolutionized sea travel and paved the way for future advances in ocean exploration and understanding of Earth's geography.