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Vanguard I, scoffed at by Russia's Nikita Khrushchev as a "grapefruit," paid rich scientific rewards: its sensitive instruments measured the earth and discovered it is pear-shaped, with a soft. hump at the North Pole and a 50-ft. depression at the South Pole. Moreover, Vanguard reported that the earth did not bulge as much at the equator as geodicists had previously estimated; since the bulge results from the earth's spin, the discovery meant that the earth's mantle is harder than had been believed. Says NASA's Dr. John Hagen, who heads the Vanguard project: "This is the wonder of this satellite business—that a satellite's orbit can tell us something so basic about the earth we are standing on.'7 The most spectacular performance made yet by a space-research vehicle was that of Pioneer V, which last week was still sending radio data from 12 million miles away as it continued on its lonely journey toward the orbit of Venus. About 25,000 miles from earth, Pioneer V found a current of electricity (also noted by Explorer VI), carrying perhaps 5,000,000 amperes, flowing around the planet. Farther out, Pioneer V's magnetometers showed that the earth's magnetic field terminates at about 56,000 miles—almost twice as far as had been calculated. 'There is a theory," says a scientist at Space Technology Laboratories in Los Angeles, "that the solar wind hits the field boundary in puffs, and not continuously. When the puff hits, there is an inelastic collision—the solar particles stop and stay." This is something like being hit in the face with cotton candy; it doesn't bounce off. And it would explain the magnetic boundary being farther out than expected.
Still farther out, Pioneer V reported a weak magnetic field that apparently has nothing to do with earth. What causes it? Perhaps a ring current in the sun's corona? Or the field of the galaxy itself? The mystery is one that fascinates space scientists.
Cloud Camera. However much such way-out wonders may entrance the men who are making space science their life, and however deeply the research vehicles may probe into the bade but dreadfully complex mysteries of the solar system, they are hardly calculated to set the world's nonscientific citizens to dancing in the streets. Still, there is one U.S. research satellite—which is also a "use" vehicle—whose function can excite scientist and layman alike: it is Tiros I, the weather-observing spacecraft launched in April of this year.
_Since then, Tiros has taken and transmitted back to earth thousands of photographs of the cloud formations that help make the world's weather. Its TV camera is still working, and indeed it is almost too successful: U.S. meteorologists have been inundated by information about cloud patterns never before available to them, and it may take them years to analyze the findings. There was, for instance, a gigantic cyclonic formation off Hawaii, 2,000 miles across, a phenomenon never before observed. When the real meaning of such patterns is analyzed and applied to weather forecasting and perhaps weather control, the impact can be not only of immense importance to military forces but of consuming interest to all the world's flying, farming, fun-seeking peoples.