Arthur von Auwers discovered NGC 6503 = Au 37 on 22 Jul 1854 with his 2.6" Fraunhofer refractor while a 15-year old student at Gottingen University. He showed the new nebula to his friend Friedrich Winnecke, who was also a student there at the time. Winnecke, using a 9.6-inch Fraunhofer refractor in 1856 in Berlin, described "..a beautiful object; very bright, slightly brighter in the middle and extraordinarily extended from north preceding to south following, 3-4' long, 50" wide." Auwers observed NGC 6503 again on 19 Feb 1862 with the Konigsberg heliometer and wrote "bright 3'-4' long, at most 1' wide; gradually brighter in the middle. There appears to be a faint star in the northern part, which makes the nebula nearly look like a double nebula." Auwers' description was published in his 1862 list of 50 new nebulae.

William Herschel missed NGC 6503, mainly because of the high northern declination which he only searched in his later sweeps, though he did discover NGC 6434, which is about 3° from NGC 6503.

200/250mm - 8" (6/27/81): moderately bright, very elongated, high surface brightness. A mag 9 star is 4' E.

400/500mm - 17.5" (6/11/88): very bright, large, very elongated 3:1 NW-SE, large brighter core. The surface has a mottled appearance. A mag 13.5 star lies 2.2' NNE of center. Located 3.9' W of mag 9 SAO 8937.

Notes by Steve Gottlieb