Dear colleagues,

on Saturday May 6, some minutes before 14 hours of European continental
summertime, a very bright fireball appeared over south-western Poland and
Silesia. It was visible from whole Poland, Czechia and Slovakia. Tens of
thousands of people saw the magnificient spectacle. 

To be able to compute its atmospheric visible trajectory, enough accurate
data for triangulation are needed. Just a tiny proportion of observers is
able to reconstruct the event and to measure the needed pairs of
angles for some points of the trajectory: their azimuths (geographic ones,
measured from the north, preferably) and angular heights (elevations over
a horizontal plane) -- angular heights are usually measurable just if some
trees or buildings appeared close to the path.  

The data we have up to now are sparse: just the last part of the
trajectory observed from the Observatory of the Comenius University near
Modra (Little Carpathians), Observatory in Rimavska Sobota and my
measurements made with help of one witness from Brno and one from a
village south from it.

The result is that the final blast and fragmentation took place probably
some thirty kilometres over the Moravian-Silesian Beskides (longitude 18.4
degrees, latitude 49.5 degrees). 

The beginning of the visible trajectory is still very uncertain, it could
have been two to three hundred kilometres northwards, in azimuth of some
340 degrees from the end of the fireball, perhaps near Poznan. The
trajectory was rather horizontal. 

Further observations from places near to the path could yield much
more accurate knowledge. Especially observers from the meteorological
stations could be able to report (perhaps after a reconstruction)
positions of some points on the (linear) trajectory, preferably including
estimates of their uncertainties.

People close to the path could have witnessed even some sounds,
either simultaneous (electrophonic) or arriving some minutes (up to ten
minutes) later. Accurate timings of those sounds would be most welcome. 

You see, dazzling daytime meteors are extremely rare over densely
inhabited areas, and the investigation of this central European one is a
tremendous opportunity to understand them better. 

Please, give this appeal to those people, who in the needed time 
(saturday 6. May 2000, 13:50 to 14:00 CEST) watched the sky, or may have
heard the subsequent sounds. 

(More information could appear provisionaly at http://svetlo.astro.cz)

Yours sincerely,
Jenik Hollan

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                                Jan Hollan
              N. Copernicus Observatory and Planetarium in Brno
Kraví hora 2, CZ - 616 00 Brno                        +420 (5) 41 32 12 87

                                   home:
Lipová 19, 602 00 Brno                                         43 23 90 96

                 member of the Society for Sustainable Living
             and volunteer of the Ecological counselling Veronica
Panská 9, 602 00 Brno, Czechia                  fax:  +420 (5) 42 21 05 61

e-mail: hollan@ped.muni.cz             http://astro.sci.muni.cz/pub/hollan
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