While a petition is circulating among planetary scientists to protest the IAU resolution on the definition of planets and dwarf planets, I think they did a pretty good job, even though there are some ambiguities. When faced with life’s difficult questions, the answer can usually be found in Star Trek. In this case, if the U.S.S. Enterprise came to a solar system just like ours, the report on the system from Mr. Spock to Captain Kirk would be “Eight planets with two debris swarms, one between the fourth and fifth planets, and one beyond the eighth planet.” I think Pluto is definitely the most interesting unexplored object in the solar system, but it’s just plain different than the other 8 planets.