泡湯淋流星雨

如計劃星期五晚出發，星期六凌晨一點去泡，最好提早訂位。因週末想去的人很多。以下資料出自http://www.imo.net/calendar/2006/fall Geminids (GEM) Active: December 7 —17; Maximum: December 14, 10h45m UT (? = 2622) 2.3h; ZHR = 120; Radiant: a = 112, d = +33; Radiant drift: v8 = 35 km/s; r = 2.6; TFC: a = 087, d = +20 and a = 135, d = +49 before 23h local time, a = 087, d = +20 and a = 129, d = +20 after 23h local time ( > 40 N); a = 120, d = -03 and a = 084, d = +10 ( 20 N); a = 135, d = -05 and a = 080, d = 00 ( < 20 N). One of the finest annual showers presently observable. This year, the waning crescent Moon rises within half an hour of 1h local time across the globe on December 14, but will be a fairly minor nuisance even so. There will be some useful dark-sky observing opportunities, especially from the northern hemisphere, as while the Geminid radiant culminates around 2h local time, well north of the equator it rises around sunset, and is at a usable elevation from the local evening hours onwards. In the southern hemisphere, the radiant appears only around local midnight or so, however. 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 favours places in the extreme Far East eastwards right across North and Central America particularly. 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 of solar longitude (about one day) ahead of the visual maximum, with telescopic results indicating these meteors radiate from an elongated region, perhaps with three sub-centres. Further results on this topic would be useful.