In 1846, researchers noticed that Uranus was wobbling in a way that confounded Newton's Law of Motion. This meant they had two options: rewrite the most time-honoured of the laws of physics, or "invent" a new planet to account for the extra gravitational pull. Compared to Newton's reputation, an eighth planet seemed much less massive and Neptune was discovered. Today scientists working in the University of Louisiana have discovered a statistical anomaly of similar proportions. Professors John Matese, Patrick Whitman and Daniel Whitmire have studied the orbits of comets for 20 years, and their recent findings have led to startling...