Friday, December 30, 2005
A dying star expels its outer layers, creating a planetary nebula . so called because it resembles a planet when seen with a small telescope. NGC 6369's blue-green ring marks the location where energetic ultraviolet light has stripped electrons from oxygen atoms in the gas.
Tuesday, December 20, 2005
This detailed picture of the Helix Nebula shows a fine web of filaments, like the spokes of a bicycle, embedded in the colorful red and blue gas ring around this dying star. The Helix Nebula is one of the nearest planetary nebulae to Earth, only 650 light years away.