The plane of the Milky Way is littered with areas of star formation; regions of the sky that glow in the light of hydrogen alpha, emitted by large clouds of excited hydrogen. Two such areas are the Eagle Nebula (M16), and the Swan or Omega Nebula (M17) as shown (north is approximately up in this image).
Both nebulae are regions of recent and ongoing star formation – and both have associated open clusters containing young, hot, luminous stars whose radiation helps to excite and illuminate the nebulae themselves.
M16 is thought to lie at a distance of approximately 7000 light years, with M17 between 5000 and 6000 light years. Also shown is the open cluster M18.
Image was taken from Domaine des Mathevies, Sainte-Nathalène, Nouvelle-Aquitaine, France on 14/15/16th Aug 2018. This is a region of sky that I can’t really image from home: the southerly declination means that it’s never particularly high above the horizon from Oxfordshire, and this pairing never makes it above the roofline of our house from my home observatory!
Image taken using a QHY163M at -15C (gain/offset 200/85), Canon 200mm f2.8L II lens with a Baader 7nm H-Alpha filter. Tracked on a Losmandy GM8.
2h50m total exposure (in 5min sub frames).
Field centred at:
RA: 18h 19m 51s
Dec: -15° 02′ 59″
Size: 3.76 x 5.12 degrees