The Swan Nebula (Messier 17, NGC 6618) is one of the brightest and most massive star-forming regions in our galaxy, located about 5,500 light-years away in the constellation Sagittarius. Also known as the Omega Nebula, the Checkmark Nebula, and even the Horseshoe Nebula, it gets its most popular name from its striking resemblance to a swan gliding across cosmic waters when viewed through a telescope. Spanning nearly 15 light-years across — and closer to 40 light-years if you include its fainter outer regions — the Swan Nebula is a vast cloud of glowing hydrogen gas and dark dust shaped by the powerful radiation and stellar winds of young, hot stars at its core.

At the heart of M17 lies the open cluster NGC 6618, where newly formed stars blaze with intense ultraviolet light, ionizing the surrounding hydrogen and giving the nebula its vivid red H-alpha glow. This makes M17 not only a stellar nursery but also one of the most photogenic regions of the Milky Way, with filaments, dark knots, and sculpted arcs that come alive in narrowband imaging. Often compared to the Orion Nebula (M42), the Swan is more distant but potentially even richer in star-forming activity, offering astronomers and astrophotographers alike a window into the process of stellar birth.

First catalogued by Swiss astronomer Philippe Loys de Chéseaux in 1745–46 and added to Charles Messier’s catalog in 1764, M17 remains a summer highlight for observers. For astrophotographers, it’s a rewarding but sometimes challenging target — its low position in northern skies makes capturing it tricky under turbulent conditions, but in dark skies it shines brilliantly. Whether through a telescope eyepiece or a carefully processed deep-sky image, the Swan Nebula reveals itself as a graceful but turbulent cradle of stars, glowing with the energy of creation.
Telescope: Celestron 9.25 EdgeHD with 0.7x reducer
Mount: Sky-Watcher EQ6R-Pro
Camera: ZWO ASI2600MM Pro
Filters: Antlia 2.5nm S,H, O and V-Pro R,G,B
Dates: May-Jun 2025

Frames:
  S2: 9h30m
  Ha: 11h50m
  O3: 10h40m
  R,G,B: 3h
Total Integration: 35h