John Herschel discovered NGC 2066 = h2939 on 12 Nov 1836 and noted "vF and S; the last of a group of 7; this nebula escaped notice sweep 748. Plate IV, fig 9." The sketch on Plate IV accurately places the 7 clusters (flipped right-left and upside down).

The entire group of clusters (NGC 2046, 2047, 2057, 2058, 2059, 2065, 2066) was sketched by Joseph Turner on 26 Apr 1876 and Pietro Baracchi on 18 Dec 1884 using the 48" Great Melbourne Telescope. Turner's sketch was published in "Observations of Southern Nebulae made with the Great Melbourne Telescope 1869 - 1885" on plate IV, figure 33. Le Sueur apparently missed this cluster in an earlier observation made on 7 Feb 1870.

600/800mm - 24" (4/9/08 - Magellan Observatory, Australia): at 260x appeared moderately bright and large, round, 45" diameter, very weakly concentrated. Located on the eastern end of a rich field of 9 NGC clusters and forms the vertex of an isosceles right triangle with NGC 2065 4.2' due south and NGC 2058 4.1' due west.

Notes by Steve Gottlieb