Free The Secret of the Martian Moons by Donald A. Wollheim

and regeneration system. When the two had the lenses and frame of their scope stowed safely into the tiny cramped cabin, they opened the emergency panel in the cruiser’s side and the little craft slipped out gently and bounced onto its own runners on the rocky surface of Phobos.
    Telders rushed out of the navigational comer of the bigger ship, handed them a sheet of paper. “Here’s the data on our various satellite speeds and positions. Mostly you can make the trip by eye, however. It’s only a short distance as they go! Take it easy when you come into Deimos though.”
    Worden and Nelson checked their own suits, hastily went over the lifeboat’s equipment as every good spaceman should and verified with their own eyes that it was all in working order. The little ship was only about fourteen feet long and its strong little engine and fuel space occupied fully half of that length. The two would have to cramp themselves into the forward seven feet along with their belongings.
    “Who’s going to drive?” asked Jim. “I know how, but it’s been quite a number of years since I piloted anything in space. Zipping through the air in explorer ramblers is about my pace today.”
    “I’ll take it up,” said Nelson, sounding more confident than he felt. “I handled these at the Space Academy only a few months ago and I’m fairly sure this will be no different.”
    His father nodded. “O.K., it’s probably better that way. The younger you are, the better your reactions and the faster your control. Just remember to keep your head and you’ll be all right.”
    So Nelson slipped into the driver’s seat and Jim piled into the space next to him, almost on his lap. They slid the transparent quarter-top closed over them, set the molecular seals. Jim spread out Telders’ notes on his lap, where he could call them off if needed to his companion.
    Nelson opened the throttle, felt the engine hum. He kicked the ground rockets into operation, felt the ship slide forward on its runners over the rocky plain. Boosting it quickly, he blasted his jump-off tubes and with a sharp jolt they were off the surface of Phobos and into space.
    “Watch that!” yelped Jim. “I almost banged my head on the top with that jackrabbit takeoff!”
    “Sorry,” Nelse murmured, busy at his controls. “I’ll get the feel of this in a moment. I forgot that we weren’t taking off against Earth’s gravity.”
    He set his teeth and flexed his fingers again. This was a test he had never really had. It was one thing to pilot this type of craft under Earth conditions in controlled testing spheres, quite another to be entrusted with it in real earnest under real space circumstances. He eased up his speed, took the little craft easily around in a wide half circle and headed it outward from the little moon.
    They could see their objective ahead of them, a tiny spot of white moving across the endless panorama of outer space. Mars’ second moon was half the size of Phobos, being only about five miles in diameter. It was nine thousand miles farther away from the red planet than the inner moon and took nearly three times as long to circle it once. As such it was even now moving slowly over the daylight hemisphere, and their mystery city objective would be in plain sight as Deimos moved through the Martian sky.
    Nelson Parr’s problem was simply to pilot the little boat outward and into the orbit of Deimos, bringing it into the same speed and cutting ahead of it as he did, so as to arrive at the little satellite at a proper landing tempo. He set up the various figures on the ship’s little automatic navigator and after it had clicked and chewed this data electronically he noted the times and alternate speeds with which he was presented. He chose the alternate that would get him there fastest, although this was always a riskier course.
    He stepped up his rocket blasts and the two men felt themselves being pushed back