  Using orbital integrations of particles ejected from Comet Halley's passages
between 1404 BC and 240 BC, the authors investigate possible outbursts of the
Orionids (twin shower of the Eta Aquariids) that may have been observed in the
western hemisphere. In an earlier orbital integration study the authors
determined there was a high probability linking probable outbursts of the Eta
Aquariid meteor shower with certain events recorded in inscriptions during the
Maya Classic Period, AD 250-900. This prior examination was the first
scientific inquiry of its kind into ancient meteor outbursts possibly recorded
in the western hemisphere where previously no pre-Columbian observations had
existed. In the current paper the aim is to describe orbital dynamics of rare
but probable Orionid outbursts that would have occurred on or near applicable
dates recorded in the Classic Maya inscriptions. Specifically, significant
probable outbursts are found in AD 417 and 585 out of 30 possible target years.
The driving mechanisms for outbursts in those two years are Jovian 1:6 and 1:7
mean motion resonances acting to maintain compact structures within the Orionid
stream for over 1 kyr. Furthermore, an Orionid outburst in AD 585 recorded by
China is confirmed.
