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Word in Space. For the moment, most scientists are concentrating on sending not man but "black boxes" into space. Humans are too heavy, bulky, ineffective and delicate to pay their way in the space vehicles of the near future. Instruments will do much better with far less demand for accommodation. Best of all, the black boxes need not get home alive. If they have radioed their findings back to earth, they can vaporize in a planet's atmosphere or wander into space never to return.
The simplest kind of instrumented space probe can gather much valuable information without landing on the moon or a planet. A picture of the back of the moon is one of the easiest prizes. Interplanetary space is by no means empty. It contains a very thin gas of unknown composition, and through it a "wind" of high-speed particles blows outward from the sun. This wind may be dangerous; it should be studied carefully before manned ships are launched deeply into space.
As the space art improves, instrumented vehicles will make soft landings on the moon, braked gently to the airless surface by retrorockets. Once they get there, they can look around with television eyes, telling the earth what they see. When the probes get good enough to tackle the planets, they can swoop into the atmosphere of Venus for a look at its unknown surface, swing around Mars looking for signs of life.
An unsolved problem is communication. It will do no good to send a space probe to Mars if communication with it is lost, as happened to Lunik soon after it passed the moon. Radio signals can cover any desired distance if given sufficient power, but the only power sources now available are heavy, short-lived chemical batteries or feeble solar batteries. To tell its story properly from the distance of Mars, a probe needs as much power as an earth-side radio station. One possibility is a nuclear battery getting its energy from radioactive materials. Another (one form of which was invented by Professor Gold) is a solar battery of gossamer-light plastic film whose large area will catch several kilowatts of solar power.
Men in Space. But instruments can never bring back as much information as a spaceship with a human crew. The difficulties of manned space flight are still enormous, and they seem to increase the longer they are studied. The recently discovered belt of Van Allen radiation that rings the earth is a serious hazard that was not dreamed of a few months ago.
But man will fly through space, hazards or no hazards. The Russians are known to be planning to put a man up in a satellite. Astronomer Alexander A. Mikhailov, director of Pulkovo Observatory near Leningrad, told a TIME correspondent last week that they are also planning a manned voyage to the moon. The biggest problem, he said, is safe return, and they do not intend to risk a man until they are sure of getting him back alive.