Draconid meteor storms
D.J. Asher and D.I. Steel
Proc. Int. Meteor Conf., Sibiu 2011, ed. M. Gyssens & P. Roggemans, IMO, 40-43 (2012)

Outbursts and storms in the October Draconid meteor shower occur because meteoroids from the parent periodic comet, 21P/Giacobini-Zinner, are not dispersed uniformly around the stream. The comet's orbital evolution has allowed meteoroidal material to be fed into the stream for the past few centuries and to be supplied for the next thousand years or more, but this depends on the nucleus continuing to be physically active. Various shower outbursts can be linked to the comet's observed activity during the past century.

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