Word: hydrogen
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Where, then, can this vast amount of energy come from? Hoyle and Fowler rule out hydrogen fusion and other nuclear reactions that go on in the sun. Such reactions do not take place suddenly enough, or provide enough energy. The only reasonable remaining source of energy is gravitation, which can grow incredibly strong when a very large amount of matter is gathered together. This energy is released when something happens that permits a large mass of material to fall toward a center of gravitational attraction...
Relativistic Limit. A galactic explosion starts, say Hoyle and Fowler, when a large mass of gas accumulates in the center of a galaxy's nucleus. The gas behaves like a very large star, equal in mass to 100 million suns. For a while it burns hydrogen and changes it to helium just as normal stars do, and the temperature in its center rises to 70 million degrees. Then the star burns its helium, forming heavier elements. Its central temperature rises to 500 million degrees, while its powerful gravitation causes it to shrink toward its superheated middle. In spite...
...have profound effects. Physicists Jerome Pressman, William Reidy and Winifred Tank of Geophysics Corp. of America have calculated that 25 tons of fluorine can scavenge out of the earth's atmosphere all the free electrons that now make long-distance radio communication possible. Some 25,000 tons of hydrogen, which is soon to be burned in just such vast quantities, could screen off the sun's ultraviolet light, changing the atmosphere's temperature, causing unpredictable and perhaps unpleasant effects on the earth's weather and climate...
Missed Targets. Everyone likes Rover -the White House, the Atomic Energy Commission, the National Aeronautics and Space Administration. Senator Anderson insists that nuclear-powered rocketry is as important to U.S. security as the hydrogen bomb. Moreover, the theory behind Rover is disarmingly simple. In present U.S. and Russian space rockets, thrust is produced by the combustion of highly volatile chemical propellants. In Rover, a small nuclear reactor will generate heat that will expand hydrogen. This, in turn, will be directed out of the rear of the rockets to provide thrust. Because the reactor and the hydrogen take up relatively little...
Radio astronomers are particularly intrigued by the special waves given off by cold hydrogen floating between the stars. These waves are a little longer than 21 cm. long when they leave the hydrogen cloud where they are generated. If they are slightly shorter than that when they are measured by an earthly radio telescope, this means that the hydrogen cloud must be moving rapidly toward the earth. If the waves are longer, the cloud is moving away. So the 21-cm. waves provide a handy tool for measuring the speed of the hydrogen clouds that form an important part...