"You're really strong. I'm no match for you at all..."
After climbing out of the crater, Goku had already been knocked out of his Super Saiyan 3 state by the overwhelming impact. He scratched his head, his eyes shining with excitement.
He had never been the type to lose heart over defeat. On the contrary, learning that there were opponents stronger than himself only thrilled him.
Perhaps it was precisely that optimistic, positive, never-say-die Martial Arts spirit that allowed Goku to reach the pinnacle.
"Your combat technique is quite good. Your only weakness is that your base power is still a little low."
Lu Li spoke sincerely as well. He had noticed that Goku's foundation was excellent. Perhaps it was the training he had undergone under Master Roshi as a child that had taught him the principles of controlling power long ago.
Moreover, Goku had never been the kind-hearted person who enjoyed destruction. Having consciously protected Earth in battle for many years, he had developed the good habit of controlling his power and concentrating it on a single point.
Though he was not yet completely proficient, it was enough in ordinary battles to keep him from losing control and destroying Earth.
In Dragon Ball battles, the most dangerous thing when powerful fighters clashed was not actually fists or kicks, but energy blasts. Energy blasts were harder to control, and if one went off target and struck a planet, that planet could be at risk of being vaporized.
That was why, aside from the Kamehameha, Goku basically never used energy blasts against his enemies. Even when he used the Kamehameha, he adjusted the angle so that it would not hit Earth.
What? You were asking whether a fired Kamehameha might hurt other planets out in space?
Goku probably could not think