The eruption of Mt. St. Helens in Washington State 37 years ago was a spectacular event. Upwelling of magma caused the mountain to be forced slowly and strongly from below. On the morning of 18 May, a huge landslide occurred on the north slope face of the mountain. Rock, timber, snow and ice, slid down the face. The event allowed the volcano to release pressure and begin its eruption.
Ash was projected high in the sky and was caught in the high altitude westerly winds. The dense cloud of ash drifted east blocking out the midday sun across the state. Ash settled down on communities causing confusion and havoc.
In the path of the settling ash was Manastash Ridge astronomical observatory run by the Dept. of Astronomy of the Univ. of Washington. Douglas Geisler was working at the observatory throughout the night of the 17th into the early morning hours of the 18th. He said the skies were excellent for telescope observations. He went to bed at about 5 am.
A loud ‘boom’ barely interrupted his sleep. He went back to sleep until about noon. When he got up to go outside, it was dark.
“Yikes! – There is no day. It’s completely black; thick, inky black with visibility ~10 feet (with a flashlight), & it stinks. This is the end of the world.”
In the logbook for the 19th, he noted for the record the sky condition was black & smelly. He also noted he lost 6 hours of observing due to volcano (good excuse, huh?)
He thought he might be the last survivor of the war as he remembered hearing a ‘boom’. He turned on the radio and heard ‘cha cha’ music. Why was the world playing music at the end of the world? Eventually the radio station from Yakima said that Mt. St. Helens ‘blew its wad.’ He was relieved.
It remained dark until mid-afternoon. Several inches of ash settled on the ground. Visibility improved to about 1/2 mile by dusk. He covered the telescope and instruments to prevent damage. He took some pictures of the dome and surroundings thinking he might make a lot of money on his story. But, he never followed through.
How I See It 
Your post prompted me to check on the latest science of the Earth’s internal heat. I note from Wikipedia that it comes from two roughly-equal sources: radioactive heat and primordial heat left over from the formation of the Earth. Much more is known now than when I was young, Thanks, Jim
This is a good animation of some of the dynamics involved with those internal heat sources. In the Pacific NW the Juan de Fuca plate is sliding under the N. American plate giving rise to Rainier, Hood, and St. Helens. https://youtu.be/ryrXAGY1dmE
You are right about how much is known these days.
Jim, what is with all the heavy rains down your way. You are at it again.
The 2-day total in my rain gage this morning was 4.5″. I saw on the weather radar yesterday evening that one of those frontal boundaries was perfectly positioned to move longitudinally (northeasterly) right over Joplin. It was a good example of how nature can surprise by acting outside the statistical average. Fortunately, our 17-year-old roof held up just fine. 😊
HI Jim, I remember this well. We even had some of the ash and haze up our way.
It was a powerful event. And, it will happen again someday. Have a good long weekend.
I was interested in Douglas Geisler’s notes. Those were new to me, and pretty compelling. That would be quite an experience, and his initial concern makes sense. On the other hand — can you imagine hearing that music on the radio and thinking, “What the….?”
Coincidentally, a reader and I were talking dandelions a couple of days ago, and she posted a link to her Pacific NW variety. When I was reading about it, I found a note that it likes disturbed ground, and was one of the first plants to recolonize Mt. Saint Helens after the eruption. Those dandelions are tough! No wonder they’re so hard to get out of a yard.
Geisler’s log entries really caught my imagination. I think he was relieved to find out the end was not near.
Dandelions are superbly adapted. Another one is the chicory plant. They thrive along roadsides in the harshest of disturbed ground. Rocks, fumes, road salt, you name it. “We love it here. No competition.”
Geisler’s experience would’ve made for a good episode of the old Twilight Zone television show.
My uncle, Donald Wilson, survivor of the sinking of the Yorktown at Midway, lived at rural Naselle, WA, for years after the war. (When we went out with Grandma to visit them in 1962–from Iowa, he quickly built a bathroom onto the house!) They sent some Mount St. Helen’s ash. Our son had a treasure hunt for friends one day and each took home a small bottle of the ash. Yes, I still have one.
Good for you. It sounds like Donald may have been a character. Good that he got that bathroom ready.
And, thank you for the many visits and likes on my posts. 🙂
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