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Active:£ October 6 ¡ª10
Maximum:£ October 9; 4h30m UT (¦Ë = 195¡ã4 - but see below)
ZHR =£ periodic - up to storm levels
Radiant:£ ¦Á = 262¡ã; ¦Ä = +54¡ã
Radiant drift:£ negligible
v¡Þ =£ 20 km/s
r =£ 2.6
TFC:£ ¦Á = 290¡ã; ¦Ä = +65¡ã and
 ¦Á = 288¡ã; ¦Ä = +39¡ã (¦Â > 30¡ã N)




The Draconids are primarily a periodic shower which produced spectacular, brief, meteor storms twice last century, in 1933 and 1946, and lower rates in several other years (ZHRs ~ 20 ¡ª500+). Most detected showers were in years when the stream's parent comet, 21P/Giacobini-Zinner, returned to perihelion, as it did last in 2005 July.

In 2005 October, a largely unexpected outburst happened near the comet's nodal crossing time, around ¦Ë = 195¡ã40 ¡ª195¡ã44, probably due to material shed in 1946. Visual ZHRs were ~ 35, though radar detections suggested a much higher estimated rate, closer to ~ 150. The peak was found in radio results too, but it did not record especially strongly that way either. Outlying maximum times from the recent past have spanned from ¦Ë = 195¡ã075 (in 1998; EZHRs ~ 700), equivalent to 2007 October 8, 20h30m UT, through the nodal passage time above, to ¦Ë 195¡ã63 ¡ª195¡ã76 (a minor outburst in 1999, not a perihelion-return year; ZHRs ~ 10 ¡ª20), equating to 2007 October 9, 10h ¡ª13h UT.

The radiant is circumpolar from many northern hemisphere locations, but is higher in the pre-midnight and near-dawn hours of early October. New Moon on October 11 makes for an almost perfect observing opportunity, whatever the shower may yield ¡ª even if that is nothing detectable. Draconid meteors are exceptionally slow-moving, a characteristic which helps separate genuine shower meteors from sporadics accidentally lining up with the radiant.

 

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ÔðÈα༭:skylook