This 12,000 work eBook short read tells the story of Neptune’s discovery and what we have learned in the 180 years since then. Neptune was discovered in 1846 after two mathematicians – John Couch Adams and Urbain Le Verrier – independently predicted that only the existence of an undiscovered planet beyond the orbit of Uranus could explain the latter’s puzzling behaviour. Following Pluto’s demotion, this distant planet has regained its place as the Solar System’s outermost planet; a world so remote that despite being many times larger than Earth, it can never be seen with the naked eye.