This catalogue is  UNDER PERMANENT COMPLETION!  Please either check my homepage
for status messages or ask for regular updates.

This catalogue and any data of this catalogue can only be distributed with this
file.Any usage of the data must include the this catalogue as its source.

1. Used sources:
---------------------------------------------


* Kronk, G. W.: "Cometography - Vol. I: Ancient - 1799", 2000.
* Kronk, G. W.: "Comets - A Descriptive Catalog"
* Machholz, D.: "A Decade Of Comets"
* Rudenko, M.: "Catalogue of Cometary Discovery Positions"  in  ICQ  8,  No. 4,
  (Oct. 1986), p.117..129.
* Vsekhsvyatskii, S. K.: "Physical Characteristics of Comets"
* "Catalogue of Cometary Orbits 2001"
* IAU - Circulars
* Minor Planet Circulars (MPEC)
* Private Communication with discoverers
* ICQ - International Comet Quarterly
* Other historic sources (e.g. biographies, articles, etc.)
* Kazumi Akiyama (data on Japanese discoveries)
* Maciej Reszelski (data on Polish discoveries)
* Kazimieras Cernis  (data on  Lithuanian discoveries and  discoveries  in the 
  Republics of the former Soviet Union)
* Doug Biesecker, http://sungrazer.nascom.nasa.gov

2. Format
-------------

01-12  Short designation
13-26  Date of discovery (format YYYY_MM_DD.DDD)
27     Blank
28-34  Rightascension (2000.0) (format hh mm.m)
35     Blank
36-41  Declination (2000.0) (format ddd mm)
42     Blank
43-46  Elongation in deg and sky (E - evening, M - morning) (format dddS)
47     Blank
48     Discovery method: V - visual, P - photographic, C - CCD
49-51  Aperture of the instrument in cm
52     Instrument (ICQ-Code)
53-55  Magnification
56-57  Focal ratio
58     Blank
59-62  Diameter of the comet in arcmin (format mm.m)
63     Blank
64-67  Brightness in mag
68     Blank
69-71  Geographical place  of the discovery as country abbreviation, SAT stands
       for Satellite
72     Blank
73-75  IAU Station Code
76     An  asterisk indicates that the  station code is not  exactly identical 
       with the  place of discovery but  sufficient enough for  calculating the
       local observation circumstances.
77     Classification as amateur A
78     Rediscovery R
79-83  Source of discovery announcement:
        XXXX    IAUC
       AJXXX    The Astrophysical Journal
       NXXXX    Astronomische Nachrichten
84     Blank
85     An x means, that  there  is more  information on this  discovery in the 
       comnotes.txt file
86     Blank
87-90  Corresponding  page  number  in  "Cometography"  (Kronk).   The  capital
       indicates the volume (A = Vol. I, B = Vol II, etc.)
91     Blank
92-139 Name of the comet, in brackets the name of the  rediscoverer or the real
       discoverer

For multiple discoveries the entry is splitted into multiple lines.

3. Notes
-----------

3.1 Brightness and diameter

The values for brightness and diameter come partly  from the statements of  the
discoverers or the discovery announcements, but were also calculated and  taken
from subsequent observations. When using  these values for  analyses one always
have to be aware that brightness indications for comets are often not reliable.
There are  several reasons  for this.  For ancient  discoveries the  brightness
values are nothing more than educated guesses, which were made in  modern times
to fit the verbal descriptions of these times. Even statements like  "the comet
was as bright as Vega"  have no meaning  compared to todays  definition  of the
total  (visual) brightness of a comet.  Often such statements  referred only to
the  central  condensation  or  the  false nucleus of the comet.  But even  the
brightness  indications  of  todays comet  discoveries are  not  values without
uncertainties.  Faint comets are mostly detected by  photographic  and  now  by
electronic means (CCD). Especially for CCD discoveries of the big surveys (e.g.
LINEAR,  LONEOS  etc) this results in differences of up to even 3 or 4 mag! The
simple cause of such differences lies in the search strategy of the big surveys
which work with short integration times  and thus only  recording the innermost
condensation of the comet.
An additional effect is the different wavelength sensitivity which also  causes
the  CCD magnitudes to become often fainter than the visual ones.  Photographic
exposures also show such an effect, but not in such extent.

The brightness values in the Catalogue can be divided into 6 classes. 

1) brightness estimations  for ancient discoveries, which  reach even  into the
   20th century, 
2) brightness estimations for photographic discoveries,
3) brightness estimations for visual discoveries in the 20th century and later,
4) brightness estimations for CCD discoveries,
5) brightness estimations for satellite discoveries,
   and
6) values for brightness and diameter estimated shortly after a photographic or
   CCD discovery by visual means.

The latter values are taken from the ICQ.

       THESE VALUES HAVE NO SPECIAL INDICATION AS VISUAL ESTIMATIONS! 

It is even possible that the visual estimations  which were made  shortly after
the original discovery are not reliable since the comet may have experienced an
outburst in brightness.

Although the new  "Cometography" by Gary Kronk does in  most cases not  contain
values of the discovery brightness  for  the ancient comets anymore I have kept
in most cases the values of his previous "Comets - A Descriptive Catalogue".

        ALWAYS KEEP IN MIND THAT THE UNCERTAINTY FOR THESE VALUES
                MAY BE AS HIGH AS SEVERAL MAGNITUDES!

3.2 Positions and elongations

Positions prior to comet  C/1991 X2 (Mueller) have been converted into  equinox
2000.0.  Where no information was available on the exact discovery date it  was
assumed to be "dd.2" for discoveries in the morning and  "dd.8" for discoveries
in  the  evening.  The dates for  historic discoveries,  i.e. before the era of
astronomical telegrams or announcements, were also taken from Kronk.
For non-visual discoveries after C/1991 X2 (Mueller)  the astrometric data were
used.  If the comet was discovered visually,  then its  discovery position  was
re-calculated.  All values were obtained using the latest  orbital elements and
the GUIDE software.

3.3 Name vs. discoverer

The names for the comets used in the  Catalogue are the official names as  they
are given in the "Catalogue of Cometary Orbits". Names in brackets are credited
discoverers whose name was not officially attached to the comet  due to several
reasons.

     THEY ARE NOT OFFICIAL AND SHOULD NOT BE USED WHEN INDICATING A COMET!

First,  the official naming of comets starts in  1760.  Discoveries prior  that
year bear no name (Anonymous) except some periodic comets which were identified
later. Names in brackets are the names of the discoverers as they were credited
then. They were taken also from Kronks "Cometography".
Second,  there are some  periodic comets  which were  discovered several  times
before  the  periodic  nature was established.  Then the name  of the  original
discoverer is  also given in brackets.  (There is also  a small group of  names
which refer to the calculator of the orbit  and not to the original discoverer:
Crommelin, Encke, Halley, and Lexell.)
Third, the modern surveys have a clear impact on the comet naming. Here no name
is  given in  brackets since  in most  cases it  is not  possible to identify a
person behind the discovery.

A  special case  is the  SOHO spacecraft,  a solar  observatory in  space which
observes  the sun  in several  wavelenghts. It has discovered now more than 380
comets (end of 2001),  mostly small  Kreutz sungrazers,  which did  not survive
perihelion.  The images  of the  two coronagraphs  are freely  available on the
Internet shortly  after they  were taken  and a lot of discoveries were made by
amateurs and professional astronomers  by simply inspecting the images. Fainter
comets were  found by software  search algorithms,  too.  All these comets have
been named "SOHO".  I decided to add the names of  visual discoverers of  these
SOHO comets in brackets - maybe a bit of vanity since I have discovered some of
these comets by myself.  Comets which were  discovered by the  automated search
algorithm  got no credit.  Information about the  original discoverer  is taken
from the IAUCs and Doug Biesecker.

This table gives the comet names which are names of teams or facilities instead
of human beings.

Search programs / Observatories

Catalina            Catalina Sky Survey (USA)
BATTERS             Bisei Asteroid Tracking TElescope for Rapid Survey (Japan)
IRAS                Infrared Astronomical Satellite (1983)
LINEAR              LIncoln Near Earth Asteroid Research (USA)
LONEOS              Lowell Observatory Near-Earth Object Search (USA)
NEAT                Near Earth Asteroid Tracking (USA)
ODAS                OCA-DLR Asteroid Survey (France/Germany)
SMM                 Solar Maximum Mission Spacecraft (1980 - 1989)
SOHO                SOlar and Heliospheric Observatory (1996 - present)
SOLWIND             Spacecraft (1979 - 1985)
SPACEWATCH          Spacewatch Survey (USA)
Tsuchinshan         Tsuchinshan Observatory (China)


4. Abbreviations
------------------

a) Instrument keys

Follows  the  ICQ:  "Keys to Codes used in Tabulated Observation Format".  They
can be found at

   http://cfa-www.harvard.edu/icq/ICQKeys.html

b) Used country codes

The used  country codes  are taken  from the  international standard  ISO  3166
(except SAT for satellite discoveries).

ARG - Argentina                      ARM - Armenia 
AUS - Australia                      AUT - Austria
BEL - Belgium                        BRA - Brazil
CAN - Canada                         CHE - Switzerland
CHL - Chile                          CHN - China
CZE - Czech Republic                 DEU - Germany
DNK - Denmark                        ENG - England
ESP - Spain                          FIN - Finland
FRA - France                         GRC - Greece
HUN - Hungary                        ITA - Italy
IRN - Iran                           JAM - Jamaica
JPN - Japan                          KAZ - Kazakhstan
KOR - Korea                          LTU - Lithuania
MDG - Madagascar                     MEX - Mexico
NLD - The Netherlands                NOR - Norway
NZL - New Zealand                    PER - Peru
PHI - Phillipines                    POL - Poland
PRT - Portugal                       REU - Reunion
ROM - Romania                        RUS - Russia
SAT - Discovery via Satellite        SVK - Slovakia
SWE - Sweden                         TKM - Turkmenistan
UKR - Ukraine                        URU - Uruguay
USA - United States of America       UZB - Uzbekistan
ZAF - South Africa

c) IAU Station Codes

The IAU station codes are taken from

http://cfa-www.harvard.edu/iau/lists/ObsCodes.html

In some cases station codes were chosen whose coordinates were reasonably close
to the discovery location.  These are indicated with an  asterisk (*) following
the staion code.

5. Contact
------------

If you find mistakes or addendums to the catalogue, please give me a note.

Maik Meyer
Johann-Strauss-Str. 26
D-65779 Kelkheim
GERMANY

email: maik@comethunter.de
URL: http://www.comethunter.de