Cygnus August 2025 - Sh 2-108 (Sharpless 2-108)

 

Sadr Gamma Cygni and associated HII regions and dark dust clouds. Ha luminosity and modified RGB SHO narrowband rendering. Seestar S30 August 2025. Image Credit all versions: Kurt Thrust. Image captured from the JPO, Lowestoft, Suffolk.

"Sadr (Gamma Cygni) is a bright, yellow-white supergiant star at the center of the Cygnus constellation's "Northern Cross" asterism, marking the swan's chest, and is surrounded by the extensive Sadr Region (IC 1318) of glowing nebulae and dust, though the star and nebula are at different distances, with the nebula much farther away. It's a prominent summer night sky target, easily visible to the naked eye, and part of a rich star-forming area in the Milky Way. 

Key Characteristics:

Location: Center of the Northern Cross in Cygnus.

Appearance: A bright, yellow-white supergiant, second only to Deneb in Cygnus's brightness.

Name Meaning: "Sadr" means "chest" in Arabic, referring to its position in the swan.

Distance: About 1,800 light-years from Earth.

Surrounding Nebula: The Gamma Cygni Nebula (IC 1318) appears to surround it but is much further away (around 4,900 light-years). The images from the Hubble Space Telescope are rendered using a modified RGB-SHO palette where Sulphur II emissions are allocated to the red channel, Hydrogen alpha to the green and Oxygen III to blue". - Joel Cairo CEO of the Jodrell Plank Observatory.