"Make it six! And set your automatic pilot to 61 and 14 and 35. Now--everything's okay. Keep your chronometer reading this way--seven, nine, twelve. There'll be a few tight scrapes, but you'll hit Jupiter square on in 24 hours, if you jump your speed to 700,000 six hours from now and hold it that way." "_Square on it is, Mr. Nibley._" Nibley just lay there a moment. His voice was easy and not so high and shrill any more. "And on the way back to Mars, later, don't try to find me. I'm going out in the dark on this metal rock. Nothing but dark for me. Back to perihelion and sun for you. Know--know where _I'm_ going?" "_Where?_" "Centaurus!" Nibley laughed. "So help me God I am. No lie!" He watched the ship going out, then, and he felt the compact, collected trajectories of all the men in it. It was a good feeling to know that he was the guiding theme. Like in the old days.... Douglas' voice broke in again. "_Hey, Pop. Pop, you still there?_" A little silence. Nibley felt blood pulsing down inside his suit. "Yep," he said. "_We just gave Bruno your little note to read. Whatever it was, when he finished reading it, he went insane._" Nibley said, quiet-like. "Burn that there paper. Don't let anybody else read it." A pause. "_It's burnt. What was it?_" "Don't be inquisitive," snapped the old man. "Maybe I proved to Bruno that he didn't really exist. To hell with it!" The rocket reached its constant speed. Douglas radioed back: "_All's well. Sweet calculating, Pop. I'll tell the Rocket Officials back at Marsport. They'll be glad to know about you. Sweet, sweet calculating. Thanks. How goes it? I said--how goes it? Hey, Pop! Pop?_" Nibley raised a trembling hand and waved it at nothing. The ship was gone. He couldn't even see the jet-wash now, he could only feel that hard metal movement out there among the stars, going on and on through a course he had set for it. He couldn't speak. There was just emotion in him. He had finally, by God, heard a compliment from a mechanic of radar-computators! [Illustration: _Nibley raised a trembling hand and waved it at nothing._] He waved his hand at nothing. He watched nothing moving on and on into the crossed orbits of other invisible nothings. The silence was now complete. He put his hand down. Now he had only to chart that one last personal orbit. The one he had wanted to finish only in space and not grounded back on Mars. It didn't take lightning calculation to set it out for certain. Life and death were the parabolic ends to his trajectory. The long life, first swinging in from darkness, arcing to the inevitable perihelion, and now moving back out, out and away-- Into the soft, encompassing dark. "By God," he thought weakly, quietly. "Right up to the last, my reputation's good. Never fluked a calculation yet, and I never will...." He didn't.