Whoomp there it is!
After two astronomers, Urbain Le Verrier and John Couch Adams, independently calculated its predicted location, Johann Gottfried Galle found the planet Neptune 180 years ago on Sept 23, 1846.
In 1989 when Voyager 2 became the first—and so far only—spacecraft to visit Neptune, it took thousands of images of Neptune, its rings, and its moons, including this one.