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Orionids(or-ÿ -ŏ-nidz, oh-rÿ ) An active meteor shower, radiant: RA 97°, dec +15°, that maximizes on Oct. 22 with a zenithal hourly rate of about 25. The activity has been observed to change by as much as a factor of four between one year and the next. The shower has been the center of controversy firstly because it was thought that the radiant was stationary during the three weeks of activity. This view has now been abandoned: all showers have radiants that move with respect to the stars as the Earth moves along its orbit. Secondly the shower is associated both with Halley's comet and the Eta Aquarids because of similarities in orbital elements.
a meteor shower with its radiant in the constellation Orion. Linked with Halley’s comet, the Orionids are active every year in the second half of October. The Eta Aquarid meteor shower is also linked with Halley’s comet. The Eta Aqua-rids are active from the end of April to the beginning of May.