The swan or Omega Nebula is about 6,000 light years from my telescope. However it is 15 light years wide! What is amazing is we are seeing it edge on can you if we saw it face on it would be 40 light years in diameter! NGC 6618 lies embedded in the nebulosity and causes the gases of the nebula to shine due to radiation from these hot, young stars.

Celestron 9.25 fl/2350mm (525mm with HyperStar), SCT, OTA, F/10 (F/2.2 with HyperStar) ZWO ASI533 MC Pro cooled to 0°C

SC - (ASTAP - Plate solve, Center, & Sync), Live Stack, Save All, Master Bias Flat = Yes, Master Dark = Yes, ASTAP - Preprocess Stack Analyze 30% Reject Rate, Stack to Master FITS
Siril - Background Extraction, Photometric Color Calibration, Green Noise Removal, StarNet Starless Master and Star Mask, Asinh & Histogram Stretch on Starless, Starless Saturation, StarNet Star Recomposition (Star Negative Stretch), Darktable - Copyright and minor contrast, export PNG