Until very recently it was thought that the land along the Nile had been originally settled by farmers about 1000 years before that.

Even if the planet has a small internal heat source – and absorbs some sunlight, it would still not generate enough heat to register, he adds." It's a strange thing, because one of the arguments made against an undiscovered Planet X is that the telescopes available now are so powerful that it is surely not possible that they could have missed a planet ten times more massive than Earth?

It's been 10 years since Sedna was discovered, and at the time Sedna also hinted at a more distant object (4). With two objects, we now have increasingly compelling evidence that an unknown major body affected the outer solar system in the past.