How I should report fireballs?
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Data on fireballs are useful for different purposes:

  1. identification of photographed meteors (exact time required);
  2. informationen concerning color, train, fragmentation, and sound which are
     not easily obtainable by other techniques; and
  3. analysis of fireball periodicities and/or fireball radiants.

The Fireball Data Center (FIDAC) of the International Meteor Organization (IMO)
has the task to build up a wide and complete picture of the appearance of
fireballs troughout the year. This information will support the investigation
of these imposing, bright events, especially those accompanying meteorite
falls. Studies of fireball and meteorite-fall rates at mid-northern latitudes
demonstrate that possible meteorite-producing fireballs and actual meteorite
falls occur more frequently in the evening than in the morning, and also more
frequently in spring than in fall. These general conclusions should be
underpinned with further observations allowing a more detailed analysis,
including also the southern hemisphere.

For all these reasons we need a minimum of data of a fireball events. The three
important details are the correct date and time, the coordinates of the
location and the brightness of the fireball. The following key items are in a
complete fireball observation:

- date and time: in UT, important for comparison of data. Please use UT only,
       pay attention to the date!
- location and coordinates: important data for further computations, e.g. the
       zenithal magnitude, conversion of the trail coordinates from azimuth and
       elevation to right ascension and declination. Name of the location in
       original language, adding state and country.
- coordinates of the apparent path: in right ascension and declination for
       investigation of possible fireball radiants and in the case of a
       meteorite fall for the computation of the impact point/area. If you are
       not able to determined right ascension and declination you should
       report azimuth and elevation. Please note, the scale starts with
       North=360deg ... East=90deg ...
- apparent magnitude: as far as possible use astronomical magnitude classes; if
       required note an interval. In case of obervations by eye witnesses cite
       the comparisons they give and add a rough estimation (e.g. 'much
       brighter than Venus' -- estimation mag. -5 to -8).
- duration: of the visible path in seconds
- color: of the complete trail and any changes along it
- train: information about color, duration, apparent breadth, and shape
- fragmentation: number of pieces, location along the train, brightness of
       fragments
- persistent train: information about color, brightness, shape and iis
       variation, and time taken to vanish
- velocity: in degrees per second or on a scale of six ranks (0-stationary,
       1-very slow, 2-slow, 3-medium, 4-fast, 5-very fast)
- sound: all information about sound, the description as a comparison (e.g.
       rustle, roar, whizzing) and the time lapse between the optical
       observation and the appearance odf noise; if the occasion arises, the
       succestion of different noises can be defined too
- observer: name
- source and remarks: additional remarks, e.g. the souroundings of the
       observing place (important for synchronous sound recordings) metallic
       objects in the vicinity, wet/dry air, wind, etc.

Even if it not possible to give information concerning all data we would like
to receive reports. Please, always indicate which data are certain and wich are
not.
For the report of fireballs we use a special fireball report form (see seperate
mail).

     ----------------------------------------------------------------------
            International Meteor Organization * Fireball Data Center
     c/o Andre Knoefel, Saarbruecker Str. 8, D - 40476 Duesseldorf, Germany
                        phone: (+49) 211:450-719 (tape)
        e-mail: starex@tron.GUN.de (Internet)  100114,3235 (CompuServe)
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  International Meteor Organization * Fireball Data Center
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          F I R E B A L L    R E P O R T    F O R M
          =========================================

Date:    y    m    d        Time:   h    m    s  in UT!

Location:

Longitude:    deg    '    "      Latitude:    deg    '    "

                    ---------------------

                       Apparent path:

begin: RA =    deg                 azimuth  =    deg
       dec=    deg                 elevation=    deg
                          or
end  : RA =    deg                 azimuth  =    deg
       dec=    deg                 elevation=    deg


                    ---------------------

                        Description:


apparent magnitude:         mag
duration:    s
color:
trail:
fragmentation:
persistent train:
angular velocity:    deg/s,       or scale number:
sounds description:
sounds time lapse:
Observer
Remarks:

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