May 18, 1980, 8:32 A.M.: An earthquake suddenly triggered an avalanche on Mount St. Helens, a volcano in southern Washington State. Minutes later, Mount St. Helens blew the top off its peak and exploded into the most devastating volcanic eruption in U.S. history. What caused the eruption? What was left when it ended? What did scientists learn in its aftermath? In this extraordinary photographic essay, Patricia Lauber details the Mount St. Helens eruption and the years following. Through this clear accurate account, readers of all ages will share the awe of the scientists who witnessed both the power of the volcano and the resiliency of life.