This image of M17 ("The Swan Nebula", also called the "Omega Nebula, also called the Horseshoe nebula") was taken with a 20cm (8 inch) Celestron SCT, an f6.3 focal reducer, and an ST-6 CCD camera.
M17 is one of the most prominent of the diffuse nebulae. M17 was probably first noted by the Swiss astronomer De Cheseaux in the spring of 1764, and was also found independently by Charles Messier in June of the same year.