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(meteorobs) PPU : first results

Hello you all,

The very first analysis of pi-puppids observations is given at :

http://www.imcce.fr/s2p/puppids/

(please, follow : 2003 observations, first results 
<http://www.imcce.fr/s2p/puppids/2003results.html>)

We are very gratefull to all of you having observed !

Our conclusions are the following :

    Visual observations have not given positive results. This is not 
    surprising since our predictions was made for very tiny particles
    (50-100 micron). Interesting to see that some visual meteors have
    been seen in a very short time scale (Mike Begbie, South Africa) 

    Observations are not homogeneous. Many observers were not well
    situated (Northern hemisphere, and/or in far West/East regions).
    Observations above 45° N could be possible, due to the small
    encounter speed (18km/s) resulting in a shift of the apparent
    radiant (Thanks to J. Kac for this explanation). That is why there
    have been observers from these regions. The ones the best located
    (South Africa) have no radio station (we call it "Murphy's laws of
    meteor astronomy
    <http://www.orion-drustvodot si/MBKTeam/meteors/murphy.htm>"...)

    There is yet no strong evidence for a radio-outburst, because only
    one report (Marcel Schneider, Luxemburg) is in well accordance with
    our prediction. Radio observations in far East regions of the world
    (Australia, Japan) do not show any outburst too. This means that :

        * The radio outburst was shorter than expected and then, was not
          observed in that part of the world

    OR

        * There was no outburst at all. In this case, we conclude that
          small particles suffer non-gravitational effects that we did
          not take into account in our model.

    Problem : Rainer Arlt (IMO <http://www.imodot net>) recently reported
    that the maximum of the Lyrid meteor shower occured on 22nd Apr.
    2003, ZHR=16.7 +- 1.9 (but he also mentioned that there is a lack of
    data fom far East regions of the world). So this shower should have
    been observed by radio technique. But it is not the case when
    looking at online data base of radio meteors
    <http://radio.data.free.fr>. Consequently, it is hard to conclude
    about pi-puppids without other elements...

Another question is : why are there so many differences in European 
radio observations ? (without taking into account electro-magnetic 
perturbation that the Slovenian team encountered). If I was a "pure 
theorician", I would say that Marcel Schneider is the only good 
observer, but I know how hard it can be to do an experiment ;-)
Actually, I am not specialst of radio observation and/or radio processes 
in general, so I need your help...

Well, finally, there are more questions than answers, as it regularly 
occurs in science.

I guess you will be numerous by replying. Perhaps, to avoid parallel 
discussions, reply to IMO-news, so that everybody will be able to follow 
and give her/his opinion.

Thanks a lot once more to all of you ;-)

Jeremie

PS: "personnal communication" for Peter Jenniskens : thanks for having 
broadcasted the info up to South Africa ;-)

-- 
************************************************************
* Jeremie VAUBAILLON 
* Institut de Mecanique Celeste et de Calcul 
* des Ephemerides (www.imcce.fr, ex bdl.fr)
* 77 Avenue Denfert Rochereau
* 75014 PARIS 
* FRANCE 
************************************************************
* tel : +33 (0)1 40 51 22 66 
* fax : +33 (0)1 40 51 20 58
* URL : http://www.imcce.fr/Equipes/GAP/equipeGAP-jv-GB.html
************************************************************


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