Word: xenon
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...near absolute zero, researchers Donald Eigler and Erhard Schweizer were able to get individual atoms to respond to the magnet-like tug of a fine tungsten needle. But don't expect to see atom-etching booths at your local science fair. It took 22 hours to haul 35 xenon atoms across the bumpy nickel surface. And when the temperature rose above -380 degrees F, the masterpiece flew apart...
...meteorite that fell in Mexico in 1969. While the impact of a meteor slamming into the earth creates enough pressure to crystallize carbon into diamonds, the tiny samples found by the Chicago team apparently resulted from an ancient supernova. The evidence: they contained atomic forms of the gas xenon different from the kind found on earth or detected...
...diamonds, Anders suggests, came from red supergiant stars that threw off their outer coats, forming a gas shell. As the star's shell expanded outward and cooled, the carbon in it condensed and crystallized, forming diamonds. Later, when the star exploded, it created xenon that shot from the star's outer layers and caught up with the diamonds. "It's like the tortoise and hare," says Anders. "The xenon atoms overtake the diamonds and shoot right through them, becoming very securely locked...
...shock waves from an ancient supernova sparked the creation of the sun and planets, Anders concludes, "it's very likely that the material from which our solar system was formed was contaminated with these diamonds. The diamonds on earth may well be a mixture of those loaded with xenon and those without...
Like many other spectacular discoveries, Anders' finding was serendipitous. He and his co-workers had simply hoped to elaborate on the Alvarez hypothesis by detecting trace amounts of rare noble gases, like neon and xenon, in the layer of Cretaceous clay deposited during roughly the same period that the dinosaurs became extinct. They were seeking to identify the nature of the object responsible for the impact. Because noble gases collect in carbon particles, the scientists isolated the carbon in Cretaceous sediment taken from Denmark, Spain and New Zealand. To their surprise, all three samples contained carbon that had been deposited...