After this weeks earthquake, I actually think the coming disaster is going to be an eruption from Mt. Fuji. The Hoei eruption which happened in 1707 and is the last confirmed eruption of Mt. Fuji was triggered by an 8.6 earthquake.
Taken from the National Geographic, "Fuji’s last eruption ejected tons of tephra into the atmosphere. Tephra includes all solid volcanic material—not lava or volcanic gas. Tephra released by the 1707 eruption of Fuji (called the Hoei eruption) included volcanic ash and volcanic rock, such as pumice and scoria. Tephra blanketed the city of Edo (now the central part of Tokyo, more than 100 kilometers (62 miles) away)."
https://education.nationalgeographic...on-mount-fuji/
This would explain the fireballs falling from the sky.