Dukkha: Suffering
The strain built into anything that arises. Those days of suffering come first and the sky's collapse follows from them, one continuous fabric: a temple pulled down, families running for the hills, and then a star falling are the same process at different scales. On the hillside the disciples had asked for a date, and instead they are handed the shape of the ache they will have to live inside.
Anicca: Impermanence
The passing character of everything that holds together. Sun and moon are the oldest clocks people own, the things a harvest and a festival are set by, and they are the first to fail. Once the steadiest lights overhead have gone dim, nothing smaller can be counted on to keep its place.
Saṃvaṭṭa: The dissolution of a world-age
The phase in which an entire world system burns down. Seven suns rise in turn, the streams thin out, the great ocean dries, and the fire climbs high enough to take the floor out from under the shining gods, so the powers of the heavens are caught inside the wreck rather than watching from above it. Stars dropping out of the sky is what the end of an age looks like when it arrives on schedule.
Saṃvega: Urgent shock
The jolt that turns a person toward practice. Being shaken is what happens to the heavenly powers here, and the same tremor is the point for anyone watching from the ground, since the comfort of a fixed sky was on loan the whole time. Alarm that settles into steady urgency will carry a person further than any calendar of dates.
Attadīpa: Be your own lamp
The Buddha's parting instruction to make oneself the lamp and the refuge. When the moon withholds its light and the sun is put out, every borrowed light fails together, and whatever a person has lit in themselves is what remains to see by. Trained attention and the Dhamma go on burning in a room whose windows show nothing.