Read The World at the End of Time for Free Online Page B

two purposes and some of the sail’s later purposes made it, in sum, very worthwhile. The trouble with it now was that at stellar distances there weren’t very many photons for it to catch.
    The film of the sail was tough, tricky stuff. It was “one-way” plastic, and it weighed very little. But to keep it spread at all, with the dynamic force of the ship’s engines tearing at it, it needed a lot of structural support; nearly a quarter of its mass went into the struts and cables that spread it at the right orientation (complex to figure, because the thrust on the sail varied with the square of the cosine of the angle it made with the source, doubly complex because there were many sources), and the motors that changed the orientation as needed. Even so, the sail’s contribution to Mayflower’s acceleration and deceleration could be measured only in tiny fractions of one millimeter per second squared.
    But those tiny delta-Vs all added up, when you had to bring a vast ship from near relativistic velocities to relative rest in just the place you wanted to insert it into orbit. So the varying flux from the flare star mattered a lot to Captain Bu, and to everyone on the ship.
    Captain Bu wasn’t always fierce. He turned out to have a weakness for kids—at least, as long as there weren’t very many of them to get in the way. He not only didn’t chase Viktor from the bridge, he actually encouraged him to visit there. He even tolerated the Stockbridge boys there—for brief periods, until they began acting up, and always with Viktor clearly understanding that his life was held hostage if the kids got in trouble.
    Captain Bu even joined Viktor and the two boys in the gravity drum, laughing and shouting, his wispy beard flying about—and then afterward, when they were all cleaned up and hungry, he shared almond-flavored bean-curd sweets with them out of his private stock. Viktor didn’t like the bean curd much, but he did like the captain. Captain Bu was a lot better than the teaching machines (though not really, Viktor was loyal enough to believe, as good as his own father) at explaining things.
    When the bean curd was finished and the boys made less sticky, he showed Viktor and the Stockbridge kids just where everything was. “This is my ship,” he said, putting a spoon on the table before him, “and Freddy’s plate there is the star we’re heading for, six point eight light-years away. It has an astronomical name, but we just call it Sun. Like the one we left.” He made a fist and held it in the air over the table. “And my hand is the flare star, about five light-years from us, about four point six from the destination, and here”—another spoon—“is the Ark, maybe a tenth of a light-year from landing. They’ve already felt the radiation. It comes at a bad time for them, velocities are getting critical, but it won’t bother them much, I think. They’re a lot farther from the flare than from the new Sun.”
    “Where’s home?” Freddy Stockbridge piped.
    “Shut up,” Viktor said, but Captain Bu shook his head forgivingly.
    He bared those big white teeth at the boy. “That is home, boy,” he said, tapping Freddy’s plate. “The place we’re going to. I know when you said that you meant Earth, though—well, that’s back somewhere by the door.”
    And as Freddy turned to look at the door he saw his mother standing there, hesitant to invade the captain’s quarters until Bu nodded to her to come in.
    “Captain,” Marie-Claude Stockbridge said, nodding. She looked very beautiful—as always, Viktor told himself yearningly. “Viktor dear, how are you? Are my little wretches giving you any trouble today, Captain?”
    “Not a bit, Dr. Stockbridge,” Captain Bu told her stiffly. Now in the presence of an adult the smile was gone. “I do have to go back to the bridge, though,” he mentioned, and nodded them out of his room. Marie-Claude looked wryly back at the closed door.
    “Doesn’t he like