Word: cometted
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Paleontologists know plenty about the demise of the dinosaurs, not just how it happened--most likely in the aftermath of a cataclysmic comet or an asteroid impact 65 million years ago--but also the variety of species that were around at the time. But there is very little evidence about the other end of the age of dinosaurs. No one knows precisely when the "terrible lizards" arose or what the earliest dinosaurs were like...
...Comet Shoemaker-Levy 9 crashes into the planet Jupiter...
...idea that a comet or asteroid might be bearing down on Earth--as in Deep Impact and Armageddon--can be traced to this crusading geologist. Probing Arizona's Meteor Crater in 1956, Shoemaker found a form of quartz that is created only by tremendous impacts. Finding the same telltale mineral in other craters, he concluded that they had been formed not by volcanoes, as most scientists thought, but by large objects hitting Earth. It was only a matter of time, he said, before Earth would be struck again. So he launched the first organized search for big incoming objects, recruiting...
...other instruments had to be light, but the collector had to be ingenious. Although the probe will loop two times around the sun to help it match orbits with the comet, Stardust and Wild 2 will still shoot past each other at nearly 4 miles per second, 10 times as fast as a speeding bullet. In order to catch dust particles without disintegrating them, Jet Propulsion Lab engineer Peter Tsou first thought of making a trap out of Styrofoam; he figured dust would bury itself harmlessly inside. Unfortunately, says Tsou, "cosmic dust particles are so small that on Styrofoam...
...into a collector that resembles a circular ice-cube tray about a foot across. En route to Wild 2, one side will trap dust that's wafting in from beyond the solar system--another item of great interest to astronomers--and once there, it will flip to scoop up comet dust...