M 17 (OC+N)

Open Cluster + Nebula in Sagittarius
R.A.Dec.SizeMag SBCnt.StTypeDistanceChart
18h 20m 47.7s-16° 10′ 21.0″40.0′6.013.4EN+OCL; 3, 3, 3OC+N----
M 17 DSS plate
Source: POSS-2 UK Schmidt Red (STScI) | Field: 60′ × 60′

Background

M17 is the Swan Nebula (or Omega Nebula) — one of the brightest emission nebulae in the sky,  5,500 light-years away in Sagittarius. The distinctive “swan” or “2” shape comes from a bright bar of nebulosity truncated by a dark dust lane.

My Observing Notes

25-cm (Meade 10-inch LX200, The Coffee Grinder): Beautiful through the Club's 10-inch with a low-power eyepiece. A bright cloud of nebulosity with an intervening band of dust creating the illusion of a thin arc forming the swan's “neck”. A perfectly placed bright star marks the swan's eye. One of my favourites of the night.(Saturday, June 2025)

References

Charts

M 17 ultra-wide chart
Ultra-wide view (~25° field)
M 17 wide-field chart
Wide-field view with Telrad rings (4°, 2°, 0.5°)
M 17 finderscope view
Finderscope view (9×50 RACI, ~4.4° TFOV)
M 17 eyepiece view
Eyepiece view — 35 mm Panoptic on 12-inch f/5 (1.6° TFOV)