The part of “IAU Resolution 5 for GA-XXVI” that describes the planet definition, states “A planet is a celestial body that (a) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (b) is in orbit around a star, and is neither a star nor a satellite of a planet.”
I’ve been watching the latest IAU debates over the definition of a planet for a number of reasons. Of course, I’d have to memorize all those new planets, but it’ll also affect some stories I’ve written. One novel in progress (set in the future) mentions the rivalry between the settlers of Ceres and those of Vesta including their sporting events. If Ceres gets to be a planet and Vesta doesn’t, well, that’ll be an interesting escalation of the ill feelings.