“”My very excellent mother just served us nine pizzas” Do you remember what this phrase is for? It’s a mnemonic device. If you guessed that it is a sentence for remembering the order and names of the planets, then you are correct! Well, at least it was until Pluto got dropped from the planetary list! It used to be a great mnemonic device because back in the day, we had 9 planets! Poor Pluto! It’s as if one day it was one of the nine and the next day it wasn’t......