His ship fell into the sun

"Doug," he said. "I want you to promise me something."
"What?"
"Don't ever be a rocket man."
I stopped.
"I mean it," he said. "Because when you're out there you want to be here, and when you're here you want to be out there. Don't start that. Don't let it get hold of you."

- from The Rocket Man, by Ray Bradbury