Mount St. Helens erupted into Pacific Northwest history 43 years ago Thursday

Mount St. Helens had stood silent for over a century in Washington’s Cascade Range. But that changed 43 years ago Thursday when the sleeping giant woke up and erupted into Pacific Northwest history.

At 8:32 a.m. on May 18, 1980, a 5.1 magnitude earthquake rattled Mount St. Helens and the north side of the volcano’s summit began to slide down the mountain. The landslide of rock and ice was the largest in recorded history, according to the U.S. Geological Survey (USGS).

The landslide removed Mount St. Helens’ northern flank and part of the cryptodome inside the mountain, causing the volcano to depressurize and erupt. The mountain went from 9,677 to 8,364 feet tall in moments and the smoke plume climbed 60,000 feet in the air, visible from satellites in orbit around the Earth.

Fifty-seven people were killed, making it the deadliest eruption in U.S. history.

The blast sent an estimated 3.2 billion tons of ash into the sky, which covered roofs and streets around the region, causing more than $1 billion in damage. The debris from the eruption covered more than 24 miles and damaged miles of property.

The blast devastated an area about 19 miles wide from east to west and more than 12 miles north from where the summit was, according to the USGS. “Virtually no trees remained of what was once dense forest” in the inner zone extending about 6 miles from the summit, the USGS said.

Just beyond the area, all standing trees were blown to the ground and the remaining trees in the blast's outer limits were “thoroughly seared.”

Harry R. Truman, the owner and caretaker for the Mount St. Helens Lodge at Spirit Lake, was among the 57 people who died. Truman is now legendary for refusing to leave the lodge in the days leading up to the eruption.

"This is my home, it's going to have to come and get me,” Truman said in one of his last interviews.