Planetary Nebula NGC 6818 Shows a Different Face

Little Gem Nebula shows off complex, knotty filament structures with a bright, enclosed central gas bubble surrounded by larger, more diffuse gas clouds

This colourful bubble is a planetary nebula called NGC 6818, also known as the Little Gem Nebula. It is located in the constellation of Sagittarius (The Archer), roughly 6000 light-years away from us. The rich glow of the cloud is just over half a light-year across — humongous compared to its tiny central star — but still a little gem on a cosmic scale. When stars like the Sun enter retirement, they shed their outer layers into space to create glowing clouds of gas called planetary nebulae. This ejection of mass is uneven, and planetary nebulae can have very complex shapes. NGC 6818 shows knotty filament-like structures and distinct layers of material, with a bright and enclosed central bubble surrounded by a larger, more diffuse cloud. Scientists believe that the stellar wind from the central star propels the outflowing material, sculpting the elongated shape of NGC 6818. As this fast wind smashes through the slower-moving cloud it creates particularly bright blowouts at the bubble’s outer layers. Hubble previously imaged this nebula back in 1997 with its Wide Field Planetary Camera 2, using a mix of filters that highlighted emission from ionised oxygen and hydrogen (opo9811h). This image, while from the same camera, uses different filters to reveal a different view of the nebula. A version of the image was submitted to the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt

Space news (August 15, 2015) – approximately 6,000 light-years toward the constellation Sagittarius (The Archer) –

When NASA’s Hubble Space Telescope first looked at the Little Gem Nebula (NGC 6818) using the Wide Field Planetary Camera 2 back in 1997, the image obtained was done so with filters that highlighted ionized oxygen and hydrogen in the planetary nebula.

This image of the Little Gem Nebula shows off complex structures with a bright, enclosed central gas bubble surrounded by larger, more diffuse gas clouds obtained using different filters. Offering the human journey to the beginning of space and time a totally different view of this spectacular stellar object.  

Our own Sun billions of years in the future will shed its outer layers into space to create a glowing cloud of gas similar to planetary nebula NGC 6818. Space scientists believe the stellar wind created by the star at the center of this planetary nebula provides the force to propel the uneven outflowing mass.

Studying the final days of sun-like stars provides scientists with data concerning the life cycle of stars similar in size and output to the Sun. Data they can use to devise new ideas and theories to delve deeper into the mysteries surrounding the closest star to Earth.

You can find more information on planetary nebula here.

Learn more about NASA’s space mission here.

You can learn more about the discoveries of the Hubble Space Telescope here.

Learn about NASA’s New Horizons recent arrival and current exploration of Pluto.

Read about plans to take the human journey to the stars on a billion mile journey to Jupiter’s moon Europa to look for signs of life.

Learn more about main sequence stars like the Sun.