Question: who was the first to discover neptune

Phil Sutton answered on 9 Mar 2017:

Which discovery ? 🙂 Neptune was first predicted by two mathematicians independently (John Couch Adams and Urbain Le Verrier) who noticed that another planet, Uranus, was not orbiting in the correct path around the Sun. At the time and still to this day we use Newtonian mechanics to predict orbits of planets or other objects in orbits. Uranus’ orbit did not match this prediction unlike all other planets. The most obvious explanation for the incorrect orbit of Uranus was that another large planet was gravitationally tugging on Uranus during its orbit. The mathematicians managed to work out how big and where the new planet might be just from the how wrong the orbit of Uranus was.

Once they published their findings the planet was then found by astronomer Johann Gottfried Galle and was very close to the predicted location.

We are at a similar time right now though. We have noticed the same deviations away from predicted orbits of a group of minor planets / asteroids just past Pluto. Mathematical modelling has shown this could be due to a massive new planet at the very edge of the solar system. Only this time to find it will be much harder. Its much further away so will be harder to find in the sky and locate. But we do have an idea where to look and are looking right now.