NGC 5531 NGC 5418
Boo
☀13.5mag
Ø 1.8' / 24''

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William Herschel discovered NGC 5522 = H III-644 on 19 Mar 1787 (sweep 720) and recorded "vF, vS, E. 300 confirmed it, but showed 2 small round patches united, which seem to be like vF aberrations of two stars without the stars. I viewed them with many different adjustments of the focus." His position is 17 sec of RA east and 2' south (or 4.5' southeast) of UGC 9116, though the description is odd. Bigourdan measured an accurate position on 23 May 1887 (given in the IC 2 notes).

400/500mm - 17.5" (5/11/02): faint, fairly small, very elongated 3:1 SW-NE, 1.0'x0.3', weakly concentrated. Nearly collinear with a mag 11 star 2.0' SW of center.

Notes by Steve Gottlieb