Fire rain

From The Stargate Omnipedia

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Edoran term for meteors which intersect the atmosphere of Edora, creating brilliant spectacles in the sky. Roughly every one hundred fifty years Edora enters a path within an asteroid field in which the planet is susceptible to the Fire Rain impacting the surface of the planet, often billowing deposits of naquadah into the air and ruining a habitable existence on the surface.

KEY EPISODE

A Hundred Days - Daniel Jackson studies several hundred years of land development in which he determines that, at several times in history, the fire rain impacted the planet and threw naquadah deposits into the air, blocking life from continuing.