Other source:
With Vegeta stronger, and Frieza afoot, Krillin is having doubts if he and the others will be able to collect the Dragon Balls. Bulma hears from her father that Goku is already on his way to Namek. Meanwhile, Goku is training aboard his spaceship at 20x the earth's gravity. Suddenly, an asteroid collides with his ship, which aims it directly into a star. Goku is forced to summon every ounce of strength that he has in order to blast his ship back on course.
