Little Ghost Nebula
Image courtesy ESA/NASA
Backyard astronomers often make friends with the Little Ghost Nebula, officially known as NGC 6369. The object can be seen from Earth as a faint cloud surrounding the corpse of a dead star in the constellation Ophiuchus.
In this 2004 Hubble Space Telescope picture, the nebula can be seen in greater detail, revealing the evolution of gas being ejected from the dying star.
As ultraviolet radiation pours from the star, it strips electrons from atoms in the gas, ionizing—electrically charging—the closest regions and creating the bright, blue-green ring. Redder areas on the outer edges of the nebula are places where ionization is less advanced.