Shipwreck in the Sky, Eando Binder [if you liked this book txt] 📗

parachute. But his helmet was gone, ripped loose, for Dan had been breathing fresh Earth air during the long parachute descent.

They stared at him as at a dead man come alive.

"Impossible to escape?" He chuckled, repeating their babble. "That's what I thought too, until I remembered those data tables on gravity and Escape Velocity and such—how, on the Moon, the Escape Velocity is much less than on Earth. And on that tiny second moon—well, my clue was when I threw a stone into the air and it never came back."

Dan gulped hot coffee.

"I got off the moonlet myself then, got up to more than a mile above it where I was free of its feeble gravity. But I was still in the same orbit circling Earth. I'd have continued revolving as a human satellite forever, of course, but for this emergency gadget hooked to my belt."

Dan held up the metal gun with its empty tank and needle-nose half burned away.

"Reaction pistol. Fires hydrazine and oxidizer, ordinary jet-rocket principle. Aiming it toward the stars, opposite earth, its reactive blasts shoved me Earthward, thanks to Newton. I needed a speed of about one-half mile a second. The powerful little jet gun had only my small mass to shove in free space, without gravity or friction. That broke me from free-fall around Earth to gravity-fall toward Earth.

"Then I spiraled down under gravity pull. I reached lung-filling air density just in time, before my oxygen gave out. One more danger was that I began heating up like a meteor due to air friction. I flung out a prayer first, followed by my twin parachutes, designed for extreme initial shock. They held. Slowed me to a paratrooper's drift the rest of the way down."

"Wait," a puzzled pilot objected. "Your story doesn't hang together. How did you get off that moonlet? How did you get up there, a mile above it, away from its gravity? There was nobody to throw you, like a stone."

"I threw myself," said Dan. "First I ran as fast as I could, maybe halfway around that moonlet, to get a good running start. And then—"

Dan Barstow's grin then was undoubtedly the biggest grin in history....

"Well, then, since the feeble gravity couldn't pull me back again, what I really did was to jump clear off that moon."