We are living in potentially dangerous times: The B-swarm passage ~7810 BC occurred while Vulcan was near aphelion as it is now. It caused multiple (~7) impacts causing a world-wide catastrophe. The Sun (and inner planets) are at a maximum distance from the barycenter of the Sun/Vulcan system, possibly exposing us to a similar impact risk from the B-swarm's comets at 2052 +/- 72.

Vulcan's period and eccentricity can also be estimated from the past comet impacts as the induced comet swarms pass. Twenty-nine possible impact events yield 37 separate swarm period values averaging 3317 +/- 104 years (verses a 3313 year predicted period). Vulcan's period should be 3/2 times this value, or 4975 +/- 156 years (verses the predicted 4969 +/- 12 or 4972 +/- 27 year values). The eccentricity is reflected in a long followed by a short interval between impacts from the four major comet swarms. Theoretically, the interval should be around 489 +162/-250 years. The impact interval between the B' and B swarms yield about 515 +/- 67 years, close to the anticipated value. The interval between A' and A swarms impacts yield about 774 +/- 62 years. This swarm's greater spread may be due to orbital geometrical considerations. Following are the two major statistical findings of this effort.

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