"All clear, sir," Koa called.
Rip stepped inside and made a quick inspection. The box was empty except for the spaceman pilot. He put a hand on the pilot's shoulder. "On your way, Rocky. Thanks."
"You're welcome, sir." The pilot added, "Watch out for high vack."
Rip and Koa stepped out and walked a little distance away. Santos and Pederson cast the landing boat adrift and shoved it away from the anchored boat. In a moment fire spurted from the bottom tube, spreading over the dull metal and licking at the feet of the Planeteers.
Rip watched the boat rise upward to the great, sleek, dark bulk of the Scorpius. The landing boat maneuvered into the air lock with brief flares from its exhausts. In a few moments the sparkling blast of auxiliary rocket tubes moved the spaceship away. O'Brine was putting a little distance between his ship and the asteroid before turning on the nuclear drive. The ship decreased in size until Rip saw it only as a dark, oval silhouette against the Milky Way. Then the exhaust of the nuclear drive grew into a mighty column of glowing blue, and the ship flamed into space.
For a moment Rip had a wild impulse to yell for the ship to come back. He had been in vacuum before, but only as a cadet, with an officer in charge. Now, suddenly, he was the one responsible. The job was his. He stiffened. Planeteer officers didn't worry about things like that. He forced his mind to the job at hand.
The next step was to establish a base. The base would have to be on the dark side of the asteroid, once it was in its new orbit. That meant a temporary base now and a better one later, when they had blasted the little planet into its new course. He estimated roughly the approximate positions where he would place his charges, using the sun and the star Canopus as visual guides.
"This will do for a temporary base," he announced. "Rig the boat compartment. While two of you are doing that, you others break out the rocket launcher and rocket racks and assemble the cutting torch. Koa will make assignments."
While the sergeant major translated Rip's general instructions into specific orders for each man, the young lieutenant walked to the edge of the sun belt. There was no atmosphere, so the edge was a sharp line between dark and light. There wasn't much light, either. They were too far from the sun for that. But as they neared the sun, the darkness would be their protection. They would get so close to Sol that the metal on the sun side would get soft as butter.
He bent close to the uneven surface. It was clean metal, not oxidized at all. The thorium had never been exposed to oxygen. Here and there, pyramids of metal thrust up from the asteroid, sometimes singly, sometimes in clusters. They were metal crystal formations. He guessed that once, long ages ago, the asteroid had been a part of something much bigger, perhaps a planet. One theory said the asteroids were formed when a planet exploded. This asteroid might have been a pocket of pure thorium in the planet.