James Dunlop discovered NGC 1818 = D 236 = D 234? = D235? = h2749 on 3 Aug 1826 and described (for D 236) as "a small nebula, 20" diameter, with a very bright point in the centre." He observed it twice and the published position is 3.4' ENE of center. D 234 was described as "a round well-defined nebula, about 30" diameter." This entry has a single observation and the position is 8.5' SSW of center. D 235 was described as a "small round pretty well-defined nebula" and his position is 5.5' NNW of center!

John Herschel made 6 observations of the cluster with the first description from 2 Nov 1834: "vB, S, R cluster of distinct stars, mbM, 2' diameter."

600/800mm - 30" (11/4/10 - Coonabarabran, 264x): very bright, fairly large, 2.5' diameter, sharply concentrated with an intense core that is partially resolved into several very faint stars. The halo was fairly well resolved with two dozen faint stars plus some brighter mag 12-13 stars in the outer halo. Just off the southwest edge is KMHK 490, a very small non-stellar object that appeared like a close double star. NGC 1818 is the brightest of a trio with NGC 1810 6' NW and S-L 205 5' NE. S-L 205 is just a faint, diffuse glow, roughly 35" diameter. NGC 1822 and NGC 1826, a fainter pair of clusters, lie 14' NNE. NGC 1818 is a "young" blue globular (YPC), formed only 40 million years ago.

Notes by Steve Gottlieb