Reporting on the Leonids - PART I
=================================

Dear meteor enthusiasts,

The peak night of the Leonid meteor shower gets closer, and
I would like to emphasize some issues of reporting your
observations to the International Meteor Organization. The
global activity analyses of the Leonids and other meteor
showers is enormously successful. As every year, everyone 
being out for the Leonids is invited to contribute to the 
grand totals and the measurement of a precise cross-section 
through the Leonid stream.

We can distinguish four groups of observations. Each of them
is most valuable for the analysis of the Leonid shower, you
may decide which version looks suitable for your observing
plans:

(i)   Recording meteor counts per minute.
(ii)  Recording Leonids/non-Leonids per minute
(iii) Recording Leonids/non-Leonids plus magnitudes
(iv)  Recording LEO/TAU/AMO/spo plus magnitudes

During the time of the outburst, when more than say 50 meteors
per hour are visible, the majority of them are Leonids. The
error of simple counts (i) is thus small. In this first of my
messages, let's have a look at the first style:


Recording meteor counts per minute
----------------------------------
The following example is adapted from Lew's recent message about
reporting on the Leonids. Formats may be slightly different;
the important thing is that the report is complete and roughly
follows the below order:

==================
Observer: Tom KING
Place: Huntington, NY  (Lat 40.8 N, long 73.4 W)
Time: 9:45-10:46, 19 Nov 2002 UT.  [UNIVERSAL TIME = EST+5]
Effective time: 100% (no time lost to looking away or breaks)
Limiting mag.: +5.0   [measured by counting stars]
Field obstructions: none.
Direction faced: Taurus
--
ONE MINUTE COUNTS STARTING 09:45 UT
09:45   23 meteors 
09:46   17 
09:47   19        (10% cloud)
09:48   15        (30% cloud)
09:49   BREAK
09:55   18 
09:56   25 
09:57   22 
...
==================

Observer:           Only counts by single observers should be 
                    reported. If you observe in a party of several 
                    people, these observers should take their 
                    individual notes on meteors, irregardless whether 
                    two people saw the same meteor.
Place:              Give a nearby town. Geographic coordinates can 
                    be given as above, or as 40deg48'N, 73deg24'W. 
Field obstructions: Usually this means buildings or trees. Note
                    that a typical field of view has a diameter of 
                    little more than 100 degrees. If there is sky 
                    blocking near the horizon and irrelevant for your 
                    observing, keep 'none' in this line. If you have 
                    cloud moving through your field, note the rough 
                    percentage behind the minute counts (see above).
Direction faced:    A constellation name is best here. If the field
                    center changed during the observation, note it
                    among the meteor counts. If you like to give RA
                    and DEC -- even better.

09:45   23 meteors: This one-minute count refers to 09:45:00 to
                    09:45:59 inclusive. Please make sure that you
                    have a precisely set observing watch.


Observations should be sent to		namn@atmob.org

for North American observers, and to	visual@imo.net

for all other observers. Your reports then enter the global analysis
of the Leonid meteor shower.


If you have any questions, do not hesitate to discuss them here via
the meteorobs mailing list.
Coming soon: Part II, Recording Leonids/non-Leonids


Best wishes,
Rainer Arlt


--
Rainer Arlt  --  Astrophysikalisches Institut Potsdam -- www.aip.de
Visual Commission - International Meteor Organization -- www.imo.net
rarlt@aip.de
 --  phone: +49-331-7499-354  --  fax: +49-331-7499-526