This pretty planetary nebula, cataloged as
NGC 6369, was discovered by 18th century astronomer
William Herschel as he used a telescope to explore the medicinal constellation
Ophiucus. Round and planet-shaped, the nebula is also relatively
faint and has acquired the popular moniker of Little Ghost Nebula.
Planetary nebulae in general are not at all related to planets, but instead are created at the end of a sun-like star's life as its outer layers expand into space while the star's core shrinks to become a white dwarf. The transformed white dwarf star, seen near the center, radiates strongly at ultraviolet wavelengths and powers the expanding nebula's glow. Surprisingly complex
details and structures of NGC 6369 are revealed in this
delightful color image composed from Hubble Space Telescope
data. The nebula's main ring structure is about a light-year across and the glow from ionized oxygen, hydrogen, and nitrogen atoms
are colored blue, green, and red respectively. Over 2,000 light-years away, the Little Ghost Nebula offers a glimpse of the fate of our Sun, which should produce its own pretty planetary nebula only about 5 billion years from now.