Six hundred and fifty light-years away in the constellation Aquarius, a dead star about the size of Earth, is refusing to fade away peacefully. In death, it is spewing out massive amounts of hot gas and intense ultraviolet radiation, creating a spectacular object called a “planetary nebula.
Beauty is in the eye of the beholder, but it would be hard to not describe this image of NGC 6326 as anything but beautiful. The photo was taken by the Hubble Space Telescope on June 28, 2010.
There are four basic types of nebulae in the universe, three of which are diffuse nebulae, supernova remnants and dark nebulae. NGC 6326 is what is known as a planetary nebula. Planetary nebulae are formed when a red giant star runs out of hydrogen fuel to burn, and it begins shedding its outer layers in the process of becoming a white dwarf. The material expended by the host star eventually finds its way into newly-forming planetary systems.
The outpouring gas is illuminated by intense ultraviolet light. The red light captured in the photo is the glow from hydrogen gas, and the blue glow is from ionized oxygen. Sometimes this outpouring is more or less symmetric, as is the case with the Ring Nebula (also known as Messier Object 57). While created by the same processes as the Ring Nebula, NGC 6326 is not symmetric.
NGC 6326 is located in the southern constellation of Ara, the Altar. It is 11,000 light-years from Earth. The photo was taken by Hubble Space Telescope’s Wide Field Planetary Camera 2. -MAX
The Keyhole Nebula, NGC 3324, is an emission nebula located about 9,000 light years away. It is part of the larger Eta Carina Nebula, both created by the star Eta Carina, which often spits out chunks of material as it reaches its last few centuries of life.
Eta Carina is well over 100 times the mass of the Sun, and was first noticed in 1840 when the light from an explosion from the star reached Earth. It continues to be a bit of a mystery, and the entire system seems to be going through some unusual changes.