¡õ×÷Õß:

[1]

One of the finest, and probably the most reliable, of the major annual showers presently observable. This year, the waxing crescent Moon will set by mid-evening across the globe on December14 (the actual moonset timing is progressively later the further south you are), giving mostly dark skies for all observers, especially those in the northern hemisphere. The Geminid radiant culminates around 2h local time, but well north of the equator it rises around sunset, and is at a usable elevation from the local evening hours onwards, while in the southern hemisphere, the radiant appears only around local midnight or so. Even from more southerly sites, this is a splendid stream of often bright, medium-speed meteors, a rewarding sight for all watchers, whatever method they employ. The peak has shown slight signs of variability in its rates and timing in recent years, with the more reliably-observed maxima during the past two decades all having occurred within 2h20m of the time given above. The main predicted timing, coupled with moonset, favours places from central Asia eastwards across the Pacific Ocean to Alaska. An earlier or later timing would extend this best-visible zone some way eastwards or westwards respectively. Some mass-sorting within the stream means the fainter telescopic meteors should be most abundant almost 1¡ã of solar longitude (about one day) ahead of the visual maximum, with telescopic results indicating such meteors radiate from an elongated region, perhaps with three sub-centres. Further results on this topic would be useful.