"Yes, Ruth," he insisted. "No," she whispered, her voice barely audible over the static-streaked hum in his earphones. "You're wrong, Tom. You're wrong. The satellite will send us the power we need. Then we'll build our machines and teach our children." _How can you teach what you don't know?_ Tom wanted to ask, but didn't. He worked without talking, hauling the weightless tons of satellite packages into position, electronically welding them together, splicing wiring systems too intricate for his conscious mind to understand. * * * * * Twice he pulled himself back along the lifeline into the ship for capsule meals and stimulants. Finally he found himself staring at his gloved hands moving industriously within the bowels of one of the satellite packages. He stopped, suddenly aware that it was piercingly cold and totally dark except for the lamp on his helmet. He pushed away from the unfinished satellite. Two of the packages were assembled now. The big parabolic mirror and two other uncrated units hung nearby, waiting impassively. Tom groped his way back into the ship. After taking off his helmet and swallowing a couple of energy pills he said to the ship's radio: "What time is it?" The abrupt sound of his own voice half-startled him. "Nearly four a.m." It was Jason. "Earth's blotted out the sun," Tom muttered. "Getting damned cold in here." "You're in the ship?" "Yes. It got too cold for the suit." "Turn up the ship's heaters," Jason said. "What's the temperature in there?" Tom glanced at the thermometer as he twisted the thermostat dial as far as it would go. "Forty-nine," he answered. He could sense Jason nod. "The heaters are on minimum power automatically unless you turn them up. It'll warm you up in a few seconds. How's the satellite?" Tom told him what remained to be done. "You're not even half through yet." Jason's voice grew fainter and Tom knew that he was doing some mental arithmetic as he thought out loud. "You've been up about twenty hours; at the rate you're going you'll need another twenty-four to finish the job. That will bring you very close to your oxygen limit." Tom sat impassively and stared at the gray metal and colored knobs of the radio. "Is everything going all right?" Jason asked. "How should I know? Ask Arnoldsson." "He's asleep. They all are." "Except you." "That's right," Jason said, "except me." "How long did Ruth stay on the radio?" "About sixteen hours. I ordered her to sleep a few hours ago." "You're pretty good at giving orders," Tom said. "Someone has to." "Yeah." Tom ran a hand across his mouth. _Boy, could I use a cigarette. Funny, I haven't even thought about them in years._ * * * * * "Look," he said to the radio, "we might as well settle something right now. How many men are you going to let me have?" "Don't you think you'd better save that for now and get back to work?"