Word: iridium
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...scientists had defined the meter as the distance between two marks on a platinum-iridium bar kept under controlled conditions near Paris. Still, even this measurement, accurate to one part in a million, was eventually adjudged unsatisfactory. In 1960 the meter was redefined as 1,650,763.73 wave lengths of the reddish-orange light emitted by krypton 86, a rare atmospheric...
...enduring mystery-and created a scientific parlor game. Hypotheses abound to explain the extinction. Brains too small in bodies too large? Emerging mammals feasting on dinosaur eggs? Now comes evidence for another possibility. Geologist Walter Alvarez, probing an ocean canyon near Gubbio, Italy, discovered an abrupt increase in iridium in a limestone layer dating back to the dinosaurs' demise. Probable cause: some mysterious, still unfathomable extraterrestrial event...
...provide a rare, undisturbed record of reversals in the earth's magnetic field. Such fluctuations can influence climate, and possibly allow more cosmic radiation to assail the earth's atmosphere. One layer, only a centimeter thick and tracing back 65 million years, showed a sharp excess of iridium, an element 1,000 times more plentiful in otherworldly matter than in the earth's crust. The "spike" in the readings made a sobering point. "It's the first experimental evidence that something quite extraordinary happened then," says Physics Nobel Laureate Luis Alvarez, who gave...
...first a post-mortem study yielded no poison. But what doctors did find under Markov's skin was a tiny platinum-iridium pellet, 1.7 mm in diameter, with two holes, each a mere .4 mm wide, drilled in at right angles. The holes could have contained a toxic substance, either bacterial or chemical?quite possibly not traceable...
...Syed, who has been doing implants at the Los Angeles County-University of Southern California Medical Center since 1973, says that a year or more after their treatment, 23 out of 24 patients showed no recurrence of breast cancer. In France, where he has treated some 500 women with iridium implants since 1961, Dr. Bernard Pierquin of Henri Mondor Hospital in the Paris suburb of Créteil reports a survival rate of about 75% to 80% after ten years-comparable to the results of radical mastectomies...