When the Allies seized Nazi secrets, some of the German plans were revealed. Among them was one for a huge earth satellite. From this base, which would circle the earth some five hundred miles away, enormous mirrors would focus the sun’s rays on any desired spot. The result: swift, fiery destruction of any city or base refusing to surrender.
First publication of this scheme brought the usual jeers. Many people, including some reputable scientists, believed it had been just a propaganda plan that even Goebbels had discarded as hopeless.
Then the Pentagon announced the U.S. Earth Satellite Vehicle Program, along with plans for a moon rocket, The artificial satellite is to be a large rocket-propelled projectile. In its upward flight, it will have to reach a speed of 23,000 miles an hour, to escape the earth’s pull of gravity. At a height of about 500 miles, special controls will turn the projectile and cause it to circle the earth. These controls will be either automatic or operated from the ground, by radar. Theoretically, once such a vehicle is beyond gravity’s magnetism, it can coast along in the sky forever. Its rocket power will be shut off; the only need for such power would be if the satellite veered off course. A momentary burst from the jets would be sufficient to bring it back to its orbit.
Circling the earth in about two hours, this first satellite is expected to be used as a testing station. Instruments will record and transmit vital information to the earth—the effect of cosmic rays, solar radiation, fuel required for course corrections, and many other items.
A second space base farther out will probably be the next step. It may be manned, or it may be under remote control like the first. Perhaps the first satellite vehicle will be followed by a compartmented operating base, a sort of aerial aircraft carrier, with other rocket ships operating to and fro on the earth shuttle. The moon rocket is expected to add to our information about space, so that finally we will emerge with an interplanetary space craft.
The first attempts may fail. The first satellite may fall back and have to be guided to an ocean landing. Or its controls might not bring it into the planned orbit. In this case, it could coast on out into space and be lost. But sooner or later, effective controls will be found. Then the manned space ships will follow.
Once in free space, there will be no gravitational pull to offset. The space ship and everything in it will be weightless. Shielding is expected to prevent danger from cosmic rays and solar radiation.
The danger from meteorites has been partly discounted in one scientific study. (“Probability that a meteorite will hit or penetrate a body situated in the vicinity of the earth,” by G. Grimminger, Journal of Applied Physics, Vol. 19, No. 10, pp. 947-956, October 1948) In this study, it is stated that a meteorite is unlikely to penetrate the thick shell our space vehicles will undoubtedly have. However, this applies only to the earth’s atmosphere. Longer studies, using remote-controlled vehicles in space, may take years before it will be safe to launch a manned space ship. Radar or other devices may have to be developed to detect approaching meteorites at a distance and automatically change a space ship’s course. The change required would be infinitesimal, using power for only a fraction of a second.
But before we are ready for interplanetary travel, we will have to harness atomic power or some other force not now available, such as cosmic rays. Navigation at such tremendous speeds is another great problem, on which special groups are now at work. A Navy scientific project recently found that strange radio signals are constantly being sent out from a “hot spot” in the Milky Way; other nebulae or “hot” stars may be similarly identified by some peculiarity in their radio emanations. If so, these could be used as check points in long-range space travel.
Escape from the earth’s gravity is possible even now, according to Francis H. Clauser, an authority on space travel plans. But the cost would be prohibitive, with our present rocket motors, and practical operations must wait for higher velocity rocket power, atomic or otherwise. (“Flight beyond the Earth’s Atmosphere, “S.A.E. Quarterly Transactions, Vol. 2, No, 4, October 1948.)