Word: thorium
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...serious risk," he said he would seek to halt the development of plutonium as a fuel source. (It can be manufactured only under federal license.) A prototype breeder to be built on the Clinch River in Oak Ridge, Tenn., will be restricted to research employing other fuels, like thorium, which is not used in weapons. Carter will block the federal funds needed to complete a privately owned plant in Barnwell, S.C., designed to reprocess used uranium fuel into plutonium. He will also call for a "joint effort" with other nations to tighten controls over plutonium...
...commercial transaction, this may well be the atom deal of the century, as many West German businessmen boast. But it has ominous implications for international stability. Endowed with plentiful uranium and thorium deposits, Brazil could use the enrichment plant not only to obtain a concentration of radioactive isotopes sufficient to fuel a nuclear power station, but also to produce the higher concentrations required for bombs...
...remaining debris. When the rain of rocks eventually ended some 3.9 billion years ago, the moon's surface was covered by great craters and basins. Other changes were still to come. Deep within the moon, heat from the slow decay of radioactive elements like uranium and thorium gradually built up, melting the once solid interior rock. Finally, between 3 billion and 4 billion years ago, lava broke through the hard outer crust in a great spasm of volcanic activity, possibly forming some new craters and flooding the great low-lying basins to create the moon's maria...
...most significant of Venera's revelations is that the chemical composition of at least part of the surface is similar to the earth's. Venera's gamma-ray spectrometer determined that the landing area contained radioactive potassium, uranium and thorium in approximately the same ratio in which they appear in many volcanic rocks on earth. This, in turn, indicates that Venus, like the earth, Mars and the moon, is "differentiated"; that is, the planet was once hot enough for its material to soften and flow. During this period, the heavier elements settled toward the core while...
...small, lemon-sized rock from the Ocean of Storms resembled an ordinary piece of granite, but it was, in fact, unlike any earthly specimen-or any of the other lunar material brought back by Apollo 12. It contained 20 times as much radioactive uranium, thorium and potassium as comparable amounts of other moon material and was the oldest lunar specimen yet obtained. Radioactive dating tests made by Caltech Geologist Gerald Wasserburg indicated that the rock was formed 4.6 billion years ago-around the time that the moon and the planets arc believed to have been created. Scientists hope that further...