Intersection points (nodes) of Comet Encke's orbit with the plane containing the Earth's orbit, at various dates before the present (BP). During the first millenium BC up to the time of Christ, the orbit of the comet or that of its associated dust trail would have intersected that of the Earth, leading at this time to annual fireball storms of amazing intensity.

Fred Hoyle and Chandra Wickremasinghe

Earth Under Fire by Paul LaViolette