Today it is called one of the largest of the 20^th century. Within sixty hours, 29 cubic kilometers of volcanic rock were released into the atmosphere. The sound waves from the explosion reached Atlanta and St. Louis. The nearby island of Kodiak was covered with a layer of ash of 30 centimeters, and the intense acid rains that fell up to 600 kilometers away corroded the clothes of people in Vancouver. So how do we apply this cataclysm to science? This is how: during the preparation for the lunar expedition, American astronauts used the volcano surroundings to practice the landing procedure.