The discovery of an icy object slightly larger than Pluto in the Kuiper Belt last year reinvigorated the argument over whether to demote Pluto or add other planets.

• 去年在柯伊柏带发现了一颗比冥王星略大的天体，这引发了是给冥王星降级还是承认新发现的天体是大行星的争论。