The Ursid shower has broad Filament-type outbursts around the perihelion passage of parent 8P/Tuttle, but also isolated narrow outbursts at aphelion. We calculated Tuttle's dust trail encounters in the same way as for the Leonid showers. We discovered that it takes 6 centuries to change the orbit enough to bring the meteoroids to Earth's orbit. During that time, the meteoroids and comet separate in mean anomaly by about 6 years, explaining the usual aphelion accurrences. Our study predicts enhanced activity on December 22, 2000, at around 7h29m UT.
WGN, Journal of the International Meteor Organization
- Pub Date:
- December 2000