A splendid return of the Quadrantids starts the northern observers' year very well, with an expected peak around 18h20m UT on January 3/4. The waxing crescent Moon was new on 2005 December 31, and will set by mid-evening in early January, so producing no significant problems at all. From many northern locations, the shower's radiant is circumpolar, in northern Boötes, but it attains a useful elevation only after local midnight, rising higher in the sky towards morning twilight. Consequently, east Asian to Far Eastern longitudes will be the most favoured places to catch the shower's best, if the peak keeps to time. An interesting challenge is to try spotting the occasional long-pathed shower member from the southern hemisphere around dawn, but sensible Quadrantid watching cannot be carried out from such places.
The maximum time given above is based on the best-observed return of the shower ever analysed, in IMO 1992 data, confirmed by radio results in most years since 1996. The peak itself is normally short-lived, and can be easily missed in just a few hours of poor northern-winter weather, which may be why the ZHR level apparently fluctuates from year to year, but some genuine variability is probably present too. For instance, visual ZHRs in 1998 persisted for over two hours at their best. An added level of complexity comes from the fact that mass-sorting of particles across the meteoroid stream may make fainter objects (radio and telescopic meteors) reach maximum up to 14 hours before the brighter (visual and photographic) ones, so observers should be alert throughout the shower. A few, but apparently not all, years since 2000 have produced a, primarily radio, maximum following the main visual one by some 9 —12 hours. Visual confirmation of any repeat near this time in 2006 would fall ideally for sites in Europe, North Africa and the Near East.
Past observations have suggested the radiant is diffuse away from the maximum, contracting notably during the peak itself, although this may be a result of the very low activity outside the hours near maximum. Photographic and video observations from January 1 —5 would be particularly welcomed by those investigating this topic, using the PFCs and TFCs given above, along with telescopic and visual plotting results. |
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