KentuckyFC (1144503) writes "Last month, astronomers announced the discovery of the most distant body in the Solar System, a dwarf planet called 2012VP113. They also said this body's orbit was strangely aligned with several other dwarf planets in the Kuiper Belt and that this could be the result of these bodies being herded by a much larger Planet X even further from the Sun. They calculated that this hidden planet could be between 2 and 15 times the mass of the Earth and orbiting at a distance of between 200 AU and 300 AU, an announcement that triggered excited headlines around the world. Now it looks as though these predictions were wildly optimistic. It turns out that the position of Planet X can be constrained more tightly using orbital measurements of other planets. And when this data is added into the mix, Planet X can only only orbit at much greater distances, if it exists at all. The new calculations suggest that a planet twice the mass of Earth cannot orbit any closer than about 500 AU. And a planet 15 times the mass of Earth must be at least 1000 AU distant. What's more, the New Horizons mission currently on its way to Pluto, should constrain the distance to beyond 4700 AU. So any Planet X hunters out there are likely to be disappointed."