How do you get the mystery star in Deep Dark galaxy on the game Super Mario Galaxy for wii?

is there really a mystery star ive never heard of it? if there is it must be really hard to find it atcually there is. there is 1 in each world. the deep dak galaxy 1 is called boo in a box. first, find an underwater shell second, go to the sunken ship with bombs around it. hit the bombs wit da shell bI sh8king the wii remote and press zee (br8ke). activate the star launcher ad swith the gravity around by spinning at the arrow (we r in da bocks by da way) break the glass blocking da son get da bo by da son and u have 4 milaseconds to grab it or all your game prodress is lost!!!!