Word: iridium
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...This research is on the interface between inorganic chemistry and organic chemistry," Evans says. It makes use of transitional elements of the periodic table such as nickel, samarium, boron, rhodium and iridium...
...Alvarezes analyzed this clay in the late 1970s and showed it had a far higher content of the rare element iridium than ordinarily found in the earth's crust. It was this discovery that led Luis Alvarez to his momentous - insight. Comets and asteroids have high iridium content, he reasoned, and the clay layer could have been formed by the worldwide fallout of the material vaporized when an errant asteroid or, as most scientists now suspect, a giant comet smacked into the earth...
...billion) hopes to put in place by 1996 a network of 77 satellites that can relay phone calls to any spot on the planet. That means when the boss has a question, no Himalayan mountaintop or African jungle encampment will be beyond the reach of the ringing phone. Named Iridium, for the chemical element whose nucleus is orbited by 77 electrons, the Motorola plan would constitute the first global cellular system. Calls would cost $1 to $3 a minute, compared with about 50 cents a minute for cellular calls within urban systems linked by radio towers. Potential users include traveling...
...apiece), the company will need investment partners to finance the estimated $2.3 billion cost of building and launching the network of 700-lb. satellites. The firm is negotiating a joint venture with British Telecom, as well as with potential investors in Japan, Australia and Hong Kong. Motorola estimates that Iridium will need 700,000 users to become profitable. While that is roughly equivalent to the Pittsburgh white pages, it is less than 1% of the 100 million people around the world who are expected to be using cellular phones by the end of the decade...
NASA has gone to extraordinary lengths to make sure the RTGs are safe. Each of the 144 plutonium pellets in the generators, designed by General Electric, is surrounded by an iridium shell. Coated pellets are then encased by two graphite shells and finally by an aluminum shroud. The U.S. Department of Energy has spent $50 million testing the generators. In one experiment, engineers fired shrapnel traveling 700 ft. per sec. at the iridium casings. None was pierced. In another test, scientists tacked an RTG to a solid rocket booster and blew it up. No damaged graphite shells were detected...