👉Since its discovery in 1846, Neptune has made only one complete trip around the Sun. One orbit. One slow and steady journey. While countless human lives began and ended on Earth, Neptune kept traveling quietly through the dark, icy edge of our solar system. It takes Neptune about 165 Earth years to circle the Sun. When astronomers first found it, people still relied on candlelight and sailing ships. Since then, wars have come and gone, technology has transformed daily life, cities have grown,

Discovery of Neptune | How Mathematics Predicted a New World (23 Sept 1846)