(meteorobs) SPE and DAU : what is the difference?

[meteoreye at comcast.net]

Hi Karl,

The IMO video data suggests a much longer break between the showers. Sirko detected SPE activity from Sept 5-13 from near RA 48, Dec +39. DAU activity was detected only from October  6-12 from near RA 106, Dec +46. So that leaves 3 weeks of very low (if any) activity between them. 

The IAU lists SPE activity from Sept Sept 7-23 (RA 050 Dec +39; 9/12) and DAU from 9/29-10/18 (RA 84, Dec +50 10/8)

This suggests they are clearly 2 different showers, and perhaps the IMO start and end times are generous.

Wayne
-------------- Original message -------------- 
From: Karl Antier <ka.antier at wanadoo.fr> 

> Hi all ! 
> 
> Just a few questions dealing with September showers and their 
> new designations... 
> Actually, the former delta-Aurigid shower splitted into two 
> different streams : the September Perseids (SPE) and the delta- 
> Aurigids (DAU). 
> They are respectively active from 05/09 to 17/09 and 18/09 to 
> 10/10, and their characteristics are nearly exactly the same 
> (radiant drift are continuous, Vinf are equal, r-index, too). 
> If I well understand, the split was made because two maxima 
> seem to appear in the data recorded (the first at lambda=166.7 deg, 
> and the second at lambda=186 deg). My question is thus to know 
> why it could not be possible that those two showers are the 
> same with a major maximum and a smaller one later ? Is one 
> of them (or both) related to different known parent-bodies ? 
> What are really the difference between the two sources that 
> make the differenciation justified? 
> Second, there seem to be some general complex activity in the 
> Perseus/Cassiopea/Auriga/Aries region at that time. Does anyone 
> have a list of possible radiants that have been observed by the 
> past, but didn't receive any confirmation since ? 
> 
> Thank you very much in advance for your answers ! 
> Clear skies ! 
> Karl 
> 
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