A Gamma Cygni Masterpiece
IC 1318 is a vast emission nebula surrounding the bright star Sadr (Gamma Cygni). Although Sadr appears to be at the center of the nebula, the star is actually much closer to Earth (1,800 light-years) than the nebula itself (4,900 light-years). The nebula is divided into several parts by prominent dark dust lanes, the most famous being the 'Butterfly' shape. This region is a violent cradle of star formation, where the intense radiation from massive hidden stars ionizes the surrounding hydrogen gas, causing it to glow with a deep red hue.
Imaging Challenges
- • Managing the extreme brightness of Sadr: The star is a magnitude 2.2 giant that can cause massive halos and reflections in fast optics.
- • Revealing the dark nebulosity (LDN 889) that provides the 'body' of the butterfly against the glowing background.
- • Separating the delicate Ha structures from the overwhelming density of the Milky Way star field.
The dark lane dividing the 'wings' of the Butterfly is a dense molecular cloud called LDN 889, which is so thick it completely blocks the light from the stars and gas behind it.