Dragonball Kai episode 18

Mr. Popo comes from out of nowhere and says hey and ask can one of you come with me so Bulma goes with Mr . Popo to look at Kami's old house but when they find and get inside they find out that it is not a house it is a spaceship. So Bilma and Mr. Popo test it to see it can fly. So Mr. Popo tells it to go to a planet and it did go to that planet at very fast speed. So they head back to earth and tell everyone and Bulma ask who wants come? Krillin and Gohan want go with Bulma. Bulma ask Mr. Popo to come he says no. But he says I can teach you how to speak namek. So Bulma study namek for ten day and it is time to head to planet Namek.