William Herschel discovered NGC 5023 = H II-664 = h1559 on 9 Apr 1787 (sweep 725) and recorded "pB, mE from sp to nf, about 5' l and 3/4' br." JH made two observations and his mean position is accurate. NGC 5023 is one of the flattest NGC galaxies.

400/500mm - 17.5" (4/21/01): moderately bright, large, thin edge-on streak SSW-NNE, 4.0'x0.4', slightly brighter center. Member of nearby group LGG 347 along with M51! A 1' pair of mag 10/11 stars lies 9' NW.

Notes by Steve Gottlieb