It was 40 years ago this week that Mount Saint Helens erupted, the biggest eruption in U.S. history, completely changing the shape of the mountain.
On the morning of Sunday May 18, 1980, an earthquake started the eruption, which lasted for several days, and sent an enormous plume of smoke, ash, and rock 80,000 feet into the atmosphere. Â The blast reached over 670 miles per hour, and put out as much explosive force as 26 megatons of TNT.
Mt. St. Helens on the morning before the eruptionÂ
The same view of the mountain, after the devastating eruption
The Atlantic has a great article showing historical photos from that day and the days that followed. Here are some of our favorites below.
