5618 5616
Cen
☀6.3mag
Ø 10'
Drawing Bertrand Laville

10x30mm Canon IS (3/27/19 - Tasmania): fairly faint, large, roundish, no obvious resolution. Alpha Centauri is in the field 1.2° ESE.

James Dunlop discovered NGC 5617 = D 302 = h3570 on 8 May 1826 with his homemade 9-inch speculum reflector and described "a cluster of small stars of mixt magnitudes, considerably congregated towards the center, 4' or 5' diameter." His position is just 2' southwest of the center of the cluster (well within the borders). John Herschel made 3 observations, first recording on sweep 578, "Cl VI. v rich; irreg R; pm comp M, but scattered at borders; 15' there are 3 stars 10m; 5 or 6 11m; the rest below 11m."

300/350mm - 13.1" (2/20/04 - Costa Rica): ~75 stars are irregularly distributed over a 10' region. The stars have a wide range of magnitudes from 10 to 14.5 and the cluster is dense in spots. Many of the stars are organized into strings with most arranged along a fairly rich string of stars running ~NNE-SSW. Additional groups of stars lies to the east and west. The cluster is easily located 1.2° WNW of Alpha Centauri between Alpha and Beta. The planetary He 2-111 lies 26' ESE.

Notes by Steve Gottlieb