Charles Messier's 44 Comets

Charles Messier probably got first fascinated from a comet in 1744, still in Badonvilier, his Lorrainian hometown, as a 13-aged, when he observed the great 6-tailed comet which was subject to extensive studies by De Cheseaux.

As a young astronomer in Paris in 1758, he early became involved in the search for Halley's comet which was predicted for 1758-59. He specialized on hunting for comets, and successfully discovered about 20 of them, 13 original discoveries and 7 independent co-discoveries (but it is sometimes discussed where to put the limit; Jean-Paul Philbert tends to count comet 1801 Pons and that of 1762 Klinkenberg as another original discovery, as it occurred almost simultaneously with that of the original discoverers). Of the 50 comets of 1758-1806, when Messier actively searched for them, he observed and described a total of 44. A translation of his personal notes is available.

Below follows a table of the 44 comets Messier observed professionally:

No  Comet                Desig. new  old    Messier  Messier observed         d t  Disco. Date Discoverers
                                                 
(0) Anonymus             C/1743 X1   1744    -       1744                     ?    1744        ?, De Cheseaux
 1  De la Nux            C/1758 K1   1758    1758    14-Aug-1758 02-Nov-1958 31 c  26-May-1758 De la Nux
 2  P/Halley             1P/1758 Y1  1759I   1759    21-Jan-1759 01-May-1759 47 c  25-Dec-1758 Palitzsch
 3  Great comet          C/1760 A1   1759III 1760 1  08-Jan-1760 30-Jan-1760  6 c  07-Jan-1760 -many- (Chevalier)
 4  Messier              C/1760 B1   1759II  1760 2  26-Jan-1760 18-Mar-1760 22 !  26-Jan-1760 Messier
 5  Klinkenberg          C/1762 K1   1762    1762    28-May-1762 05-Jul-1762 20    17-May-1762 Klinkenberg
 6  Messier              C/1763 S1   1763    1763    28-Sep-1763 24-Nov-1763 29 !  28-Sep-1763 Messier
 7  Messier              C/1764 A1   1764    1764    03-Jan-1764 11-Feb-1764 16 !  03-Jan-1764 Messier
 8  Messier              C/1766 E1   1766I   1766 1  08-Mar-1766 15-Mar-1766  8 !  08-Mar-1766 Messier
 9  P/Helfenzrieder      D/1766 G1   1766II  1766 2  08-Apr-1766 12-Apr-1766  5 c  08-Apr-1766 Helfenzrieder 
10  Messier              C/1769 P1   1769    1769    08-Aug-1769 01-Dec-1769 42 !  08-Aug-1769 Messier
11  P/Lexell             D/1770 L1   1770I   1770    14-Jun-1770 03-Oct-1760 47 !  14-Jun-1770 Messier
12  Great comet          C/1771 A1   1770II  1771 1  10-Jan-1771 20-Jan-1771  4 c  10-Jan-1771 -many- (incl. Messier)
13  Messier              C/1771 G1   1771    1771 2  01-Apr-1771 15-Jun-1771 48 !  01-Apr-1771 Messier
14  P/Biela              3D/1772 E1  1772    1772    26-Mar-1772 03-Apr-1772  4    08-Apr-1772 Montaigne
15  Messier              C/1773 T1   1773    1773    12-Oct-1773 14-Apr-1774 71 !  12-Oct-1773 Messier
16  Montaigne            C/1774 P1   1774    1774    18-Aug-1774 25-Oct-1774 41    11-Aug-1774 Montaigne
17  Bode                 C/1779 A1   1779    1779    19-Jan-1779 19-May-1779 63 c  06-Jan-1779 Bode
18  Messier              C/1780 U2   1780I   1780 2  27-Oct-1780 28-Nov-1780 13 !  27-Oct-1780 Messier    
19  Mechain              C/1781 M1   1781I   1781 1  30-Jun-1781 16-Jul-1781 14    28-Jun-1781 Mechain
20  Mechain              C/1781 T1   1781II  1781 2  10-Oct-1781 05-Nov-1781 12    09-Oct-1781 Mechain
21  P/Pigott             D/1783 W1   1783    1783    27-Nov-1783 21-Dec-1783 13    19-Nov-1783 Pigott 
22  Great comet          C/1783 X1   1784    1784    03-Feb-1784 25-May-1784 13    24-Jan-1784 -many- (Cassini)
23  Messier-Mechain      C/1785 A1   1785I   1785 1  07-Jan-1785 16-Jan-1785  6 !  07-Jan-1785 Messier
24  Mechain              C/1785 E1   1785II  1785 2  13-Mar-1785 16-Apr-1785 14    11-Mar-1785 Mechain
25  P/Encke              2P/1786 B1  1786I   1786 1  19-Jan-1786              1    17-Jan-1786 Mechain
26  Herschel             C/1786 P1   1786II  1786 2  01-Aug-1786 26 Oct 1786 43                C.Herschel
27  Mechain              C/1787 G1   1787    1787    11-Apr-1787 20-May-1787  6    10-Apr-1787 Mechain
28  Messier              C/1788 W1   1788I   1788 1  25-Nov-1788 29-Dec-1788 20 !  25-Nov-1788 Messier
29  P/Herschel-Rigollet  35P/1788 Y1 1788II  1788 2  03-Jan-1789 06-Jan-1789  2    21-Dec-1788 C.Herschel
30  Herschel             C/1790 A1   1790I   1790 1  19-Jan-1790              1    07-Jan-1790 C.Herschel
31  P/Tuttle             8P/1790 A2  1790II  1790 2  10-Jan-1790              7    09-Jan-1790 Mechain
32  Herschel             C/1790 H1   1790III 1790 3  01-May-1790 09-Jun-1790 45    17-Apr-1790 C.Herschel
33  Herschel             C/1791 X1   1792I   1791    26-Dec-1791 28-Jan-1792 12    15-Dec-1791 C.Herschel
34  Gregory              C/1793 A1   1792II  1793 1  01-Feb-1793 14-Feb-1793  6    10-Jan-1793 Gregory, Mechain
35  Perny                C/1793 S1   1793II  1793 3  27-Sep-1793 08-Dec-1793 25    24-Sep-1793 Perny  
36  Messier              C/1793 S2   1793I   1793 4  27-Sep-1793 07-Jan-1794    !  27-Sep-1793 Messier
37  Bouvard-Herschel-Lee C/1797 P1   1797    1797    16-Aug-1797 30-Aug-1797 13    14-Aug-1797 Bouvard
38  Messier              C/1798 G1   1798I   1798 1  12-Apr-1798 24-May-1798 27 !  12-Apr-1798 Messier
39  Bouvard              C/1798 X1   1798II  1798 2  07-Dec-1798 12-Dec-1798  4    06-Dec-1798 Bouvard
40  Mechain              C/1799 P1   1799I   1799 1  10-Aug-1799 25-Oct-1799 44    07-Aug-1799 Mechain
41  Mechain              C/1799 Y1   1799II  1799 2  28-Dec-1799 06-Jan-1800  5    26-Dec-1799 Mechain
42  Pons                 C/1801 N1   1801    1801    12-Jul-1801 21-Jul-1801  5 c  12-Jul-1801 Pons, Messier, Mechain, Bouvard
43  Pons                 C/1802 Q1   1802    1802    30-Aug-1802 05-Sep-1802  7    26-Aug-1802 Pons
44  Pons                 C/1804 E1   1804    1804    11-Mar-1804 17-Mar-1804  6    07-Mar-1804 Pons

Key:

No: Messier's numbering for "his" comets (i.e., those he observed)
Comet: Comet Name/Discoverer[s]
Desig.: Comet Designation: New IAU desgination; Old style "Final" designation: year and Roman number for perihelion passage; and Messier's designation
Messier observed: Dates between Messier observed the comet
d: Number of days (nights) Messier saw the comet
t: Type of discovery (if any): "!": Original discovery, "c": Independent co-discovery, "?": Perhaps an independent co-discovery
Disco. Date: Discovery Date
Discoverers: Name(s) of (original) discoverer(s)

Additional Resources and Notes on some of these comets:

2. 1P/Halley (1758 Y1, 1759I Palitzsch): Charles Messier and Comet Halley; Messier's Memoir and observations, Phil. Trans LV, 294 (1765); Gary Kronk's Comet 1P/Halley page; More info and links on Comet 1P/Halley
7. C/1764 Messier (C/1764 A1, 1764 Messier): Messier's observations, Phil. Trans LIV, 151 (1764)
8. C/1766 Messier (C/1766 E1, 1766I Messier): Messier's observations, Phil. Trans LVI, 57 (1766)
9. D/1766 Helfenzrieder (D/1766 G1, 1766 Helfenzrieder-Messier): Messier's observations, Phil. Trans LVI, 57 (1766); Gary Kronk's Comet D/1766 G1 Helfenzrieder page
10. C/1769 Messier (C/1769 P1, 1769 Messier): Bessel obtained an orbital period of 2090 years for this comet.
11. D/1770 Lexell (D/1770 L1, 1770I Messier): This comet had become short-period of only 5.6 years by being captured by Jupiter in 1767. Its next return occurred in 1776 but in daylight so that it was not observed. In 1779, it was again perturbed by Jupiter and has not returned since, as it probably was ejected from the inner solar system..
Gary Kronk's Comet D/1770 L1 Lexell page
12. C/1771 "Great Comet" (C/1771 A1, 1770II "Great Comet"): Messier's observations, Phil. Trans LXI, 104 (1771)
14. 3D/Biela (3D/1772 E1, 1772 Montaigne); (3D/1805 V1, 1806I Pons): This comet was found to have a 6.62-year period (the 3rd periodic comet) by Biela in 1826, split in two pieces in January 1846, one of them recovered last in 1852 (last observation Sep 29). Later meteor showers have been associeted with it. In 2001 it was noted (by S. Nakano) that Comet P/2001 J1 (NEAT) had a similar orbit, giving room for speculations that it might be associated with 3D/Biela in some way. (IAUC 7635)
Gary Kronk's Comet 3D/Biela page
17. C/1779 Bode (C/1779 A1).: Chart of its track or path online.
25. 2P/Encke (2P/1786 B1, 1786I Mechain); (2P/1795 V1, 1795 Herschel): The 1795 aparation (Caroline Herschel's discovery) was not observed by Charles Messier, because of years of trouble in France. Gary Kronk's Comet 2P/Encke page; Images of 2P/Encke (JPL)
31. 8P/Tuttle (8P/1790 A2, 1790II Mechain): Gary Kronk's Comet 8P/Tuttle page

References:

Jean-Paul Philbert, Charles Messier. Le furet des cometes. Editions Pierron, 2 rue Gutenberg, 57206 Sarreguemines, France, 2000. In French.
Notes On My Comets, by Charles Messier, 1808. Origianl now at Paris Observatory.