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.