D/1783 W1 (Pigott); C/1766 E1 (Messier);
D/1766 G1 (Helfenzrieder)
click on
the image for a
larger view (you will be redirected to my pbase-pages).
On this chart also the famous
nebula in Triangulum, M33, is drawn.
M33
Interesting link on this
subject:
Giangi
Caglieris:
C/1766 E1 (Messier) & D/1766 G1 (Helfenzrieder)
http://web.infinito.it/utenti/c/caglieris_gm/comete/1766/comete_1766.htm