When Mount St. Helens erupted in the morning of May 18, 1980, a freelance photographer named Robert Landsberg was within four miles of the summit documenting the event. Robert had been visiting the grumbling mountain since April, and had made dozens of successful trips hiking and climbing to various vantage points to capture the changing volcano that had been erupting for the past several weeks.

On Saturday evening, May 17, Robert camped near the volcano and wrote in his journal, “Feel right on the verge of something.” Aside from his gut feeling, there was nothing on scientific instruments that volcanologists had placed in the vicinity of the volcano to measure everything from the rate of bulge movement, to sulfur dioxide emission, and ground temperature, to indicate the catastrophe that was about to follow.