There may actually be a ninth planet in our solar system after all. Astronomers at Caltech recently presented evidence for a large, gas-giant, planet in a 20,000 year orbit around our sun. They have been quoted as saying, "We have felt a great disturbance in the force." This only adds to the crazy nature of this announcement; but they were not referring to Luke Skywalker's famed Force, but rather the gravitational force that keeps all of the planets and dwarf planets in motion around our sun. Their research suggests that the existence of such a planet, in this large elliptical orbit, is one of the best explanations for the measured orbits of the dwarf planets in the Kuiper Belt. Their argument is presented in an enlightening YouTube video and one of the scientists has been interviewed by CBC's Bob McDonald on the program "Quirks and Quarks." The mass of the planet is said to be greater than that of Earth but less than the mass of Neptune and it is perpetually "very distant" in the solar system. It has not yet been seen with a telescope; but is inferred from its interaction with the features of the Kuiper Belt.
What are the implications of such a discovery? Where should we point our telescopes to begin to look for this planet? There are certain constraints on where this planet could be, but that still leaves a large area to be scanned. The current position in its orbit will be unknown until it can be visualized. This research also invites questions related to the planet’s proximity to other planets in our solar system. What perturbations (dare I say, “disturbances in the force”) will be noted when this planet swings by after a long journey away from the other planets and dwarf planets in our solar system? Might it have noticeable effects on the physics, chemistry, and biology of Earth? Gravity is a relatively weak force but its influence acts over very large distances.
For now, I congratulate Mike Brown and Konstantin Batygin and other contributing researchers for their work in this area. May they inspire many more “planet-hunters.”