Searching for Planet 9

For decades, students were taught that the ninth planet was Pluto. Now, since Pluto is officially a “dwarf planet,“ there are only eight. But nonetheless, there may be a new “Planet 9.“ It could be five times more massive than planet Earth, and so far from the Sun that it would take 10,000 years to orbit the star. Does it really exist? Fascinating new research forces us to reconsider our beliefs.