Alaskans were rocked by a huge volcanic eruption June 6, 1912. The Novarupta volcano blew its top at approximately 1 p.m. Although no modern sensing equipment existed, scientists have deemed the explosion as the largest such event of the 20th century. Residents are marking the anniversary with poster contests, field trips to the site and educational lectures.
* The volcano was previously unknown until the massive explosion. The mountain is six miles west of Mount Katmai on the Alaska Peninsula across from Kodiak Island, according to the Associated Press.
* The eruption was heard in Juneau, approximately 750 miles to the east, Geology.com reports.
* The area surrounding the volcano became known as the Valley of Ten Thousand Smokes because of hot ash covering streams and waterways in the valley caused water to superheat and turn to steam.
* Novarupta blasted ash and dust 100,000 feet into the air. Temperatures within the cloud reached as high as 2,000 degrees.
* Up to 700 feet of the valley was covered in ash surrounding the volcano. An estimated three cubic miles of material exploded from the vent caused by the volcano. The discharge was 45 times greater than that of the eruption of Mount St. Helens in 1980.
* The top of Mount Katmai collapsed, forming a 2 1/2-mile-wide caldera filled with water 800 feet deep. Scientists aren't sure why magma didn't go through the top, instead flowing to another spot.
* There were no deaths directly linked to the explosion as the Alaska Peninsula was sparsely populated at the time. Thousands of animals died and salmon populations took a decade to recover.
* The choking air might have been a contributing factor in the death of an elderly woman in the Kodiak region who already had tuberculosis.
* For two days after the explosion on Kodiak Island, a person was unable to see a lantern held at arm's length. Clothes disintegrated on clotheslines after acid rain fell in Vancouver, British Columbia, the U.S. Geological Survey reports.
* The ash cloud spread as far away as North Africa two weeks after the eruption. Residents in California, Virginia and Europe also reported seeing ash high in the atmosphere, according to the Alaska Volcano Observatory.
* The major eruption lasted continuously for three days. The ash cloud was 1,000 miles long as atmospheric winds took particulate matter and spread it eastward into Canada.
* During summer months, tourists can take bus rides through the Valley of Ten Thousand Smokes. People can see big chunks of pumice along the beach of Kodiak Island. The pumice used to be volcanic ash that congealed together into larger pieces and solidified. The lava flow is still apparent in satellite imagery and overhead pictures.
William Browning is a research librarian.