Word: uranium
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...universe at between 8 billion and 12 billion years. But other experts insisted they knew of stars that were at least 14 billion years old--obviously a problem, since stars can't be older than the cosmos. Using the VLT, though, observers have measured minute traces of radioactive uranium and thorium in the oldest stars--a technique akin to radiocarbon dating--and proved that they're more like 12 billion years old (the age of the universe, meanwhile, is now estimated at 14 billion years...
...East is moving beyond the stone stage. An "administration official" quoted by the New York Times uses the phrase "August, 1914." Is this tiny place about to reconfirm the twentieth century's logic of disastrous disproportions, whereby a seemingly miniscule cause (a Serb zealot at Sarajevo; an atom of uranium; an obscure housepainter in Vienna) brings on apocalyptic effects...
...engine would have to deliver about a megawatt of power for every pound of weight of the ship. There is no way an engine that small and that powerful could keep itself cool. Even if the fuel is something exotic like antimatter, carrying far more energy than sunlight or uranium, the problem of cooling the engine remains insuperable. Travel to the stars within this century, using any kind of engine we know how to build, is not going to happen...
...report's author, Matthew G. Bunn, the Kennedy School's assistant director of the Science, Technology and Public Policy Program, said surplus stores of plutonium and highly enriched uranium (HEU) have posing an increased threat to U.S. security. Both plutonium and HEU can be used to make nuclear bombs...
Bunn also recommends the HEU be mixed with low-grade uranium which, while making the uranium unusable in bombs, would still be useful as power-reactor fuel...