Rocket Ship Galileo Read Online Free PDF Page A

keeping your lips buttoned. You’ll understand why, later. Now here is the idea: All my life I’ve wanted to see the day when men would conquer space and explore the planets—and I wanted to take part in it. I don’t have to tell you how that feels.” He waved a hand at the book shelves. “Those books show me you understand it; you’ve got the madness yourselves. Besides that, what I saw out on your rocket grounds, what I see here, what I saw yesterday when I sneaked a look in Art’s lab, shows me that you aren’t satisfied just to dream about it and read about it—you want to do something. Right?”
    “Right!” It was a chorus.
    Cargraves nodded. “I felt the same way. I took my first degree in mechanical engineering with the notion that rockets were mechanical engineering and that I would need the training. I worked as an engineer after graduation until I had saved up enough to go back to school. I took my doctor’s degree in atomic physics, because I had a hunch—oh, I wasn’t the only one!—I had a hunch that atomic power was needed for practical space ships. Then came the war and the Manhattan Project.
    When the Atomic Age opened up a lot of people predicted that space flight was just around the corner. But it didn’t work out that way—nobody knew how to harness the atom to a rocket. Do you know why?”
    Somewhat hesitantly Ross spoke up. “Yes, I think I do.”
    “Go ahead.”
    “Well, for a rocket you need mass times velocity, quite a bit of mass in what the jet throws out and plenty of velocity. But in an atomic reaction there isn’t very much mass and the energy comes out in radiations in all directions instead of a nice, lined-up jet. Just the same—”
    “‘Just the same’ what?”
    “Well, there ought to be a way to harness all that power. Darn it—with so much power from so little weight, there ought to be some way.”
    “Just what I’ve always thought,” Cargraves said with a grin. “We’ve built atomic plants that turn out more power than Boulder Dam. We’ve made atomic bombs that make the two used in the war seem like firecrackers. Power to burn, power to throw away. Yet we haven’t been able to hook it to a rocket. Of course there are other problems. An atomic power plant takes a lot of shielding to protect the operators—you know that. And that means weight. Weight is everything in a rocket. If you add another hundred pounds in dead load, you have to pay for it in fuel. Suppose your shield weighed only a ton—how much fuel would that cost you, Ross?”
    Ross scratched his head. “I don’t know what kind of fuel you mean nor what kind of a rocket you are talking about—what you want it to do.”
    “Fair enough,” the scientist admitted. “I asked you an impossible question. Suppose we make it a chemical fuel and a moon rocket and assume a mass-ratio of twenty to one. Then for a shield weighing a ton we have to carry twenty tons of fuel.”
    Art sat up suddenly. “Wait a minute, Uncle Don.”
    “Yes?”
    “If you use a chemical fuel, like alcohol and liquid oxygen say, then you won’t need a radiation shield.”
    “You got me, kid. But that was just for illustration. If you had a decent way to use atomic power, you might be able to hold your mass-ratio down to, let’s say, one-to-one. Then a one-ton shield would only require one ton of fuel to carry it. That suit you better?”
    Art wriggled in excitement. “I’ll say it does. That means a real space ship. We could go anywhere in it!”
    “But we’re still on earth,” his uncle pointed out dryly. “I said ‘ if .’ Don’t burn out your jets before you take off. And there is still a third hurdle: atomic power plants are fussy to control—hard to turn on, hard to turn off. But we can let that one alone till we come to it. I still think we’ll get to the moon.”
    He paused. They waited expectantly.
    “I think I’ve got a way to apply atomic power to rockets.”
    Nobody stood up. Nobody cheered. No