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Re: (meteorobs) Re: North Apex and Leonid meteors
> > 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.
As this sounds a little as a draw-back of the IMO shower
list, I'd like to comment here. The axep source in general
is a geometric result of the Earth's motion. Liek snow falkes
start to focus in front of a car driver. Even a random
distribution of particles causes an apex source. So this
is not a shower and is not listed as such. The splitting
into two branches has its reason in perihel precession
of near-ecliptic particles; it's a weird story, and I think
I am not the best in explaining it.
> 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.
Yes, thanks Lew for the clarification. In fact in these years
of enhanced Leonid activity, I will also utilize LEO observations
from date prior to and after these dates. Say Nov 10-25. But
in these cases, reliable plotting observations should have been
done to reduce sporadic pollution.
Best wishes,
Rainer
--
Rainer Arlt -- Astrophysikalisches Institut Potsdam -- www.aipdot de
Visual Commission - International Meteor Organization -- www.imodot net
rarlt@aipdot de -- phone: +49-331-7499-354 -- fax: +49-331-7499-526
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