Word: geologist
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Dates: during 1970-1979
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These perplexing questions may now have been answered by two scientists using a standard aerodynamic formula. Assuming that Pteranodon weighed only 40 Ibs. (it had an extremely delicate skeleton), Geologist Cherrie D. Bramwell and Physicist G.R. Whitfield of the University of Reading in Berkshire, England, used the formula to calculate that the beast had to attain an air speed of only 15 m.p.h. to take off. In winds above that velocity, they report in Nature, Pteranodon would only have needed to spread its wings to become airborne, easily taking off from level ground or the crest of a wave. "Thus...
...particles were 4.6 billion years old -the apparent age of the moon itself -most of the rocks were about 1 billion years younger. How could there be such a huge age gap between material picked up only a few feet apart? "This is a major puzzle," says Rice University Geologist Dieter Heymann. One small rock fragment, though, was considerably older than the others: 4.44 billion years. Caltech Geologist G. J. Wasserburg, who calculated its age, believes that still older rocks dating back to the very creation of the moon will probably be found in the unexplored lunar highlands...
...late Princeton geologist Harry Hess provided an imaginative answer to the puzzle. Refining a rough idea suggested a generation earlier, Hess proposed that the earth's mantle is really a giant convection system. Like hot air in a room, he suggested, material heated by radioactive elements in the earth's interior slowly rises out of a relatively fluid layer of the earth's mantle called the asthenosphere. This lava surfaces at the mid-ocean ridges; hence, the higher water temperatures. As it flows away from the ridges, it hardens into a more rigid layer called the lithosphere...