James Dunlop discovered NGC 4439 = D 300 on 30 Apr 1826 and described "a triangular group of very small stars, about 3' long, resembling faint nebulae. A star of the 9th magnitude near the north following extremity [the bright star is NW of the cluster]." His position is 7' too far east, but the identification is certain.

JH observed the cluster on 31 Mar 1834 and noted "Cluster taken for Dunlop 300; a semi-elliptic group of stars 11..12th mag, diameter 2'."

300/350mm - 13.1" (2/20/04 - Costa Rica): at 105x, 20 stars mag 10-13 are arranged in a perfect semi-circle (180 degree arc) open towards the west, with the endpoints directly N-S. A string of three collinear stars, oriented WNW-ESE, sits right in the middle of the semicircle! A wide bright double (HJ 4524 = 8/9.5 at 30") situated less than 5' NW is aligned directly with the center of the cluster! Situated in the middle of the Southern Cross, 55' ENE of mag 3.6 Epsilon Crucis.

Notes by Steve Gottlieb