NGC 6866 (also Melotte 229, Collinder 412 and OCL 183) is a magnitude +7.6 open star cluster located 3900 light-years away in the constellation Cygnus.
The cluster was discovered by German astronomer Caroline Herschel using a 10.7 cm (4.2 inch) 24x f/6 Newtonian reflector at Datchet, Berkshire, England, on the 23rd July 1783.
Right Ascension 20h 03m 55.1s, Declination +44° 09' 33"
