Many attempts have been made to find the so-called "Planet Nine", but all have – so far – been fruitless. In a new paper, a team claims to have their own explanation: our theory of gravity is wrong.

A plush toy designed in south-west Wales could be sent to space to help astronauts establish the presence of gravity on the Moon's surface. Courtney John, 27, from Llanelli, is a finalist in a Nasa ...