It was small by volcanic standards, but massive by human ones: on this day in 1980, Mount St. Helens erupted in what the National Oceanic and Atmospheric Administration calls “the deadliest and most economically destructive volcanic event in the history of the United States.”
Though the blast generated “about 500 times the force of the atomic bomb dropped on Hiroshima,” TIME reported in a cover story, it was seen as a “middling” explosion for a volcano. Still, it killed 57 people and thousands of animals and left the mountain itself 1,300 feet lower. As TIME reported:
Today, National Geographic reports, a “baby volcano” is growing inside the crater as magma builds up in its center. While that doesn’t pose an immediate threat to the region, it is indicative that the volcano is alive and well—a fact that may be troubling to residents of the Pacific Northwest.
“The volcano is still living and breathing,” Smithsonian volcanologist Stephanie Grocke told National Geographic.