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- <text id=92TT2837>
- <title>
- Dec. 21, 1992: Fear of the Big Whopper
- </title>
- <history>
- TIME--The Weekly Newsmagazine--1992
- Dec. 21, 1992 Restoring Hope
- </history>
- <article>
- <source>Time Magazine</source>
- <hdr>
- THE WEEK, Page 25
- HEALTH & SCIENCE
- Fear of the Big Whopper
- </hdr><body>
- <p>Scientists debate earth's vulnerability to asteroids--then
- and now
- </p>
- <p> What's the world coming to? First, astrophysicists said
- comets killed the dinosaurs. Then they implicated asteroids in
- numerous other mass extinctions throughout the earth's history,
- setting the stage for the awful news in October that the comet
- Swift-Tuttle might crash into the planet in the year 2126.
- </p>
- <p> The buildup to astronomical apocalypse grows ever more
- dramatic. At the American Geophysical Union's meeting in San
- Francisco, some respected researchers suggested that a large
- space rock 10 to 20 km (6 to 12 miles) in diameter slammed into
- the earth 250 million years ago and set whole continents adrift.
- The announcement by Michael Rampino of New York University and
- Verne Oberbeck of NASA-Ames Research Center stunned fellow
- scientists, though many dismissed it out of hand. Some
- skepticism seemed warranted. Rampino and Oberbeck rely heavily
- on their supposition that certain rocks--known as tillites and
- long thought to be formed on the earth by glaciers--were
- actually the result of a celestial collision. But tillites are
- so common that other researchers scoffed at the idea.
- </p>
- <p> Finally a bit of good news: some astronomers have revised
- calculations on Swift-Tuttle, and predict that the big comet
- will breeze by us at a comfortable 15 million-mile distance. Of
- course, there is always the possibility that some other
- uncharted space rock may come crashing through the atmosphere.
- Best keep an eye out.
- </p>
-
- </body></article>
- </text>
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