When Japanese balloon bombs landed in Sonoma County, Calif., during WWII

Right around New Year’s Day, 1945, the Japanese army released an unmanned balloon from the east coast of the main island of Honshu. It was made of 600 pieces of paper glued together, in all likelihood, by schoolgirls. It measured 33 feet in diameter and when fully inflated held about 19,000 cubic feet of hydrogen. It carried several incendiary bombs. The teardrop-shaped specter crossed 6,200 miles of the Pacific Ocean in two or three days, and finally fell apart on Jan. 4, 1945, landing in an orchard off Vine Hill Road, just east of Forestville. Alberigi, now 91, estimates the contraption landed 150-200 feet from him and his father, Frank. “It fell behind a workman’s cabin,” Terence said. “We weren’t that far from it.”

Frank Alberigi’s reaction? “What the hell is it?” his son recalled.

The Alberigis didn’t know it, but the strange occurrence was part of a coordinated campaign by the Japanese military to bomb the U.S. mainland in a slow-motion, unguided onslaught. Between November 1944 and early April 1945, it is believed, the Axis power launched roughly 9,300 weaponized balloons.