On May 18, 1980, Mount St Helens erupted in the US state of Washington. The blast, which measured 5 on the Volcanic Explosively Index, has been declared as the most disastrous volcanic eruption in modern US history. An huge column rose 80,000 feet into the atmosphere and deposited ash in 11 states, killing at least 57 people and causing more than $1billion (£770million) in damage.
Scientists are now closely watching the volcano to make sure they are prepared in case the same happens again.
Amazon Prime’s “Mega Disaster: It’s Happened Before, It Will Happen Again” series revealed how a team of volcanists monitor the ticking time bomb.
Rick LaHusen, from the United States Geological Survey (USGS), detailed how they use an instrument known as the “Spider” to keep an eye on volcanic activity.
“This is a GPS antenna which receives timing signals from satellites and lets us locate exactly what is going on inside.
“The signals go into the computer system and then the data comes out at the request from computers back in the office.”
However, Dr LaHusen’s analysis of the data provided a chilling revelation. He added: “What is really phenomenal is how much rock is still coming out of the ground.
