Extreme trans-Neptunian objects lead the way to Planet Nine

In the race towards the discovery of a ninth planet in our solar system, scientists from around the world strive to calculate its orbit using the tracks left by the small bodies that move well beyond Neptune. Now, astronomers from Spain and Cambridge University have confirmed, with new calculations, that the orbits of the six extreme trans-Neptunian objects that served as a reference to announce the existence of Planet Nine are not as stable as it was thought.