Neptune was the first planet to be discovered through Mathematics alone.
Sometime after Uranus was first discovered astronomers observed that it was not following the path the planet should take according to orbital mechanics based upon its size and distance from the sun.
Scientists theorised that another planet with a greater mass must be affecting the orbit of Uranus and set about a year-long investigation to predict where this mystery planet would likely be. In 1846, based on these calculations, Astronomers found Neptune within 1 degree of the prediction.
Neptune contains the most violent storms in the Solar System with winds in excess of 1000mph whipping around its frozen surface.
Neptune’s largest moon, Triton, is in a retrograde orbit meaning that it orbits in the opposite direction to the rotation of the planet. It is thought that this is a result of Neptune capturing Triton rather than forming as a moon from remaining planet debris.