(Source: hobbymotor)
GHOST IN THE SHELL Abell 39 is a remarkably simple, spherical nebula about five light-years across and roughly 7,000 light-years distant toward the constellation Hercules. Abell 39 is a planetary nebula, formed as a once sun-like star’s outer atmosphere was expelled over a period of thousands of years. Still visible, the nebula’s central star is evolving into a hot white dwarf. (Photo: Adam Block, Mt. Lemmon SkyCenter, University of Arizona via NASA APOD)