Ionut Nedelcu from Central Bedfordshire, England
The Cygnus Loop (Sharpless 2-103), a supernova remnant whose brightest arcs form the Veil Nebula, lies about 2,400 light-years away. Its glowing filaments trace gas heated by the blast wave of a massive star that exploded roughly 10,000 years ago. The imager took 17 hours of exposure in Hα/OIII/RGB filters with a 2.6-inch refractor at f/4.8.