Word: cm
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Dates: during 1990-1999
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...miles) long, the San Andreas Fault system separates two sections of the earth's crust known as plates. Like giant rafts, these plates glide across an expanse of superheated rock, viscous as tar, that surrounds the planet's molten outer core. At the rate of nearly 5 cm (2 in.) a year, the Pacific plate to the west of the San Andreas is slowly pushing north, past the North American plate on the east. One possible result: 60 million or so years from now, a sliver of the California coast that includes the megalopolis of Los Angeles could become beachfront...
...range, more than a meter short of record-breaking territory. Then in 1988 he began improving rapidly. At the world championships in Tokyo last August, Powell came into his own. He bounded down the runway, hit the board and soared 8.95 m, eclipsing by 5 cm the "unbreakable" record set by America's Bob Beamon 24 years ago. A believer in nonstop improvement, Powell thinks he could set another record in Barcelona...
Dinosaur lore has it that Tyrannosaurus rex, the king of the giant lizards, was the meanest creature ever to roam the earth: 10 m (33 ft.) long with 15-cm (6-in.) teeth and a voracious appetite. But fossilized claw, skull and jaw bones found in a quarry in eastern Utah point to a dinosaur that, while smaller than Tyrannosaurus, was probably a whole lot nastier. Labeled the "Utahraptor" until a more suitable scientific name can be found, the 7-m (20-ft.), one-ton beast is the largest specimen ever seen of a variety of dinosaur known...
...contrast, the mirrors designed for the European Southern Observatory consist of a single, vast expanse of glass, thin (17.7 cm) and very flexible. To control wobbling and stabilize the orientation, these mirrors, like giant catcher's mitts, will be constantly readjusted by 180 computer-activated steel "fingers." A prototype mirror has already proved its worth. A flaw identical to the one that crippled the Hubble Space Telescope was easily corrected by adjusting the mirror's shape...
...control systems and more on vitreous wizardry. The 10-ton mirror he and his colleagues plan to install in Arizona -- merely a warm-up for some 8-m versions -- boasts a light-collecting surface that is nearly as wide as a house is tall, yet it averages only 2.8 cm thick. What prevents this marvel from fracturing under its own weight is a supporting truss composed of thousands of glass ribs that are cast as part of the mirror's underlying structure. Arrayed in a striking hexagonal pattern, the ribs form an airy honeycomb that confers on the mirror...