Scientists have assembled compelling new evidence that the impact of a mile-wide meteor 35 million years ago created the Chesapeake Bay. The meteor apparently hit an area that was then covered by the ocean more than 140 miles southeast of Washington. "If it happened today," said Christian Koeberl, a scientist at the University of Vienna, "Washington would probably cease to exist."

The meteor left a 55-mile-wide crater. A team led by C. Wylie Poag of the U.S. Geological Survey presented new evidence confirming the discovery at a meeting this week at the Smithsonian Institution.