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Re: (meteorobs) Re: North Apex and Leonid meteors

I think it may be worth while to keep track of the North Apex meteors to 
see if there is a rise in rates during December and January - are the 
Coma Berenicids a "good shower" or just part of the year round North 
Apex sporadics.  The North Apex meteors are just sporadics - but very 
fast ones.  Sometimes winter is very snowy and icy here or else very 
cloudy.  Also the phase of the Moon interferes. It may take several 
years observations to come to any sort of conclusion.

Paul Martsching

Lew Gramer wrote:
> Thanks to Paul and Bob for posting on this interesting thread!
> 
> 
>>The activity period for the Leonids has nothing to do with
>>the Northern Apex meteors.
> 
> 
> A final follow-up on this topic: The IMO does not recognize the
> "Northern Apex" as a shower at all, I believe - instead, the IMO
> recommends that observers merely label these as "Sporadics". And
> of course, the activity date for the Leonids is also reckoned by
> the IMO as being 14-21 November - despite this fact.
> 
> So as Bob mentions above, the short period of recognized activity
> for the Leonids is a direct result of the narrow traverse of the
> dust stream which causes the Leonids, relative to Earth's orbit.
> 
> However, as it happens the only way that we visual observers can
> CONFIRM the short activity period of the Leonids, is because our
> observations show the Leonids being lost in "sporadic pollution"
> prior to 14 November, and after 21 November. That is, before 14
> Nov and after 21 Nov, there is no statistically valid way for a
> VISUAL observer to distinguish Sporadic activity from "late" or
> "early Leonids". So in actual fact, outside of these times, the
> Leonids ARE in effect becoming confused with Bob's Northern Apex
> "radiant", as well as the many other Sporadics this time of year.
> 
> Of course, the situation may be quite different for observers who
> use other techniques like telescopic plotting, intensified video,
> or backscatter (radar) to identify shower meteors. For such more
> accurate and "deeper" (higher Limiting-Magnitude) methods, I ex-
> pect that the Leonids may show themselves statistically against
> the background of Sporadics for at least a slightly longer period?
> 
> Clear skies,
> Lew
> 
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