Back in the day Mercury, Venus, Earth, Ceres, Pallas, Vesta, Juno, Mars, Jupiter, Saturn, Uranus, and Neptune were the 12 planets. You could kinda consider Pluto to be the 13th planet, but in 1930 when it was discovered there were already over 1000 named asteroids. So Pluto is the 1146th planet.
Pallas and Vesta aren't gravitationally rounded, though. But then again, the Moon is (being much larger than Ceres). (It's just better numbered as planet 3-1.)
