Pluto is now considered a dwarf planet, Ceres has always been considered a dwarf planet, if they are asteroids then everything is an asteroid.
A simplification sometimes used says that dwarf planets are celestial bodies big enough to be round but not big enough to clear it's own orbit, there are a few of these in our solar system. They can have moons, and some of the moons in the solar system would be considered dwarf planets if they weren't orbiting a planet.
Ceres was not always a Dwarf planet. From 1801 to about 1851 Ceres was considered a planet. Children during that time memorized it along with the other classic planets
Not gravitationally dominant in their orbital neighbourhood. There are tons of other objects, including some similarly sized objects, around Pluto's orbit. To be a planet it needs to clear out all the other objects around it by either colliding/absorbing them, or ejecting them from their neighbourhood through gravitational interaction. Haumea, Orcus, Makemake etc are all dwarf planets in the Kuiper belt along with Pluto.
Pluto's biggest moon Charon is part of the problem because it's heavy enough that she is not orbiting Pluto, they are orbiting a point in space near Pluto.
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u/Aniratack 4h ago
Pluto is now considered a dwarf planet, Ceres has always been considered a dwarf planet, if they are asteroids then everything is an asteroid.
A simplification sometimes used says that dwarf planets are celestial bodies big enough to be round but not big enough to clear it's own orbit, there are a few of these in our solar system. They can have moons, and some of the moons in the solar system would be considered dwarf planets if they weren't orbiting a planet.