What Trouble with Pluto?

There is one thing I can’t understand in the ongoing “what’s a planet” saga (now set to demote Pluto, Ceres and anything else apart from the 8 pre-1930 classical planets)

Say, if the previous proposal had been accepted and we were presented with 12 planets: what was wrong with that?

The New York Times went as far as to define it an “abomination

Let me rephrase that: in-between bombings, volcanic eruptions and Dick Cheney’s declarations about anti-Iraq-war campaigners being al-Qaeda complicits, the NYT editors have found the space&time to say that to expand the definition of “planet” is an “abomination culturally

Edwin Hubble discovered in 1923-24 that unfathomable numbers of Galaxies populate the Universe. Did he ever have to think that having more than a handful of Galaxies would have been any kind of “abomination“?


On the other hand there is something we are going to miss if there are only 8 planets in our System. Simply, there will be fewer targets to reach.


As for the current proposal, it is way too elaborate and so it defeats itself.

For example if a planet is “by far the largest body in its local population“, and “the local population is the collection of the objects that cross or close approach the orbit of the body in consideration“, I can imagine plenty of objects beyond Neptune whose orbit does not cross or close approach much of anything else (what is in fact the meaning of “close“?)

Also, what is wrong with Ceres, that is way larger than any other asteroid, and moves in an orbit with little inclination and eccentricity?


Finally, that proposal depends on the current theories on the formation of the Solar System. Do we really have to change the definition of “planet” every time we improve our science?