The Dolpin Nebula (SH2-308), captured here through narrowband filters with RGB stars, is the expanding remnant of an exploded star. It lies below the celestial equator in the constellation Canis Major, which means it's visible low to the south when viewed from North America. 

The Dolphin head itself is made up of glowing oxygen gas, shown here in blue, while the background hydrogen, mixed with additional oxygen, provides a beautiful red background.