Word: argonant
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Chemist Willard Libby. This was followed by the invention of the potassium-argon method. Both gave scientists techniques by which they could accurately determine the age of the strata in which fossilized bones were found, and sometimes the age of the bones themselves. Using these new tools, they have determined that Java man and Peking man, now classified as Homo erectus, walked the earth more than 500,000 years...
Most of the 17 pices in the exhibit use some sort of glass rod filled with one of the "noble gasses" (you remember from chemistry: that's helium, argon, neon etc.). The chemistry teacher always called those the "inert" gasses, but Sina uses electronics to make the gas-filled rods move in all sorts of interesting ways...
...pictures show that the planet is crisscrossed by dry "riverbeds" and sinuous valleys, including a deep Grand Canyon-like depression called the Valles Marineris, that were probably carved out by running water. During Viking's descent, the lander's instruments sniffed and measured both nitrogen (3%) and argon (1.5%) in the Martian atmosphere. Nitrogen is an essential element in the molecules of terrestrial life. Also, the presence of approximately the same percentage of argon found in the earth's air suggests that Mars at one time had a denser atmosphere more conducive to the evolution of life...
...biggest surprise was the discovery of a weak magnetic field (only 1% as strong as the earth's) and an extremely thin atmosphere of helium, argon and perhaps other gases (less than 0.1% as dense as the earth's). Although the earth's magnetic field is generally attributed to the churning of molten iron in the spinning planet's core, Mercury seems to rotate much too slowly to produce such a dynamo effect. But scientists offer alternative explanations. Mercury's magnetic field may be created externally by bombardment of charged particles from the sun hitting...
...Laboratory. Shielded from all other radiation by the rock above, the detector consists of a 100,000-gal. vat of a cleaning fluid called tetrachloroethylene. A small number of incoming neutrinos collide with chlorine atoms in the fluid. The collisions convert the chlorine to radioactive atoms of the element argon, which can then be counted. Davis calculated a year ago that on the basis of what scientists know and theorize about the sun, less than one-fifth as many neutrinos are radiating from it as would be expected...