SUNSET: 
0
Photographer:
Hal Heaton
Location of Photo:
Chilescope
Date/Time of photo:
August 11, September 14, 16 and 19, 2023
Equipment:
Field-corrected ASA Newtonian telescope (aperture 0.5m, f-no 3.8); FLI ProLine 16803 CCD camera with RGB and Ha filters; 300s exposures stacked for 60, 70, 70 and 40 min, respectively; acquisition scale 0.9 arcsec/px
Description:
Silhouetted against the Galactic Bulge about a degree east of the Lagoon Nebula in Sagittarius lies a complex of emission and reflection nebulae comprising Sharpless 2-29, also known as Simeis 188. The expanding cavity at its center, carved out by the energetic O7V and B0V binary star system 11 Sgr shining brightly at the upper right, is causing interstellar material to pile up and radiate as the prominent arc-shaped cloud NGC 6559 just left of center. The diffuse red glow permeating the entire field comes from H-alpha emission by hydrogen gas, while the shimmering blue light is caused by scattering off small dust particles. Small sinuous tendrils of dust create the dark filamentary structures (B303 and B302) within the clouds. North is up and east is to the left.
