NGC 7293, the Helix Nebula
NGC 7293, better known as the Helix nebula, displays its ultraviolet glow courtesy of NASA's Galaxy Evolution Explorer (GALEX). The Helix is the nearest example of a planetary nebula, which is the eventual fate of a star, like our own Sun, as it approaches the end of its life. As it runs out of fuel, the star expels its outer envelope of gas outward to form a nebula like the Helix. The remaining core of the star is a small, hot, dense remnant known as a white dwarf.
For information about the Galaxy Evolution Explorer, go to: http://www.galex.caltech.edu.