Miller: Without a doubt the 1991 eruption of Mt. Pinatubo in the Philippines ... Data from the instruments were telemetered back to a location on Clark Air Base, which is very close to Pinatubo.

This is Mount Pinatubo, an active stratovolcano located at the tri-point of Zambales, Tarlac and Pampanga. It had remained dormant for around 600 years until that tragic day on June 15 ...