This gallery shows four planetary nebulas from the first systematic survey of such objects in the solar neighborhood made with NASA's Chandra X-ray Observatory. The planetary nebulas shown here are NGC 6543, also known as the Cat's Eye, NGC 7662, NGC 7009 and NGC 6826. In each case, X-ray emission from Chandra is colored purple and optical emission from the Hubble Space Telescope is colored red, green and blue.
In the first part of this survey, published in a new paper, twenty one planetary nebulas within about 5000 light years of the Earth have been observed. The paper also includes studies of fourteen other planetary nebulas, within the same distance range, that Chandra had already observed.
A planetary nebula represents a phase of stellar evolution that the Sun should experience several billion years from now. When a star like the Sun uses up all of the hydrogen in its core, it expands into a red giant, with a radius that increases by tens to hundreds of times. In this phase, a star sheds most of its outer layers, eventually leaving behind a hot core that will soon contract to form a dense white dwarf star. A fast wind emanating from the hot core rams into the ejected atmosphere, pushes it outward, and creates the graceful, shell-like filamentary structures seen with optical telescopes.
The diffuse X-ray emission seen in about 30% of the planetary nebulas in the new Chandra survey, and all members of the gallery, is caused by shock waves as the fast wind collides with the ejected atmosphere. The new survey data reveal that the optical images of most planetary nebulas with diffuse X-ray emission display compact shells with sharp rims, surrounded by fainter halos. All of these compact shells have observed ages that are less than about 5000 years, which therefore likely represents the timescale for the strong shock waves to occur.
About half of the planetary nebulas in the study show X-ray point sources in the center, and all but one of these point sources show high energy X-rays that may be caused by a companion star, suggesting that a high frequency of central stars responsible for ejecting planetary nebulas have companions. Future studies should help clarify the role of double stars in determining the structure and evolution of planetary nebulas.
These results were published in the August 2012 issue of The Astronomical Journal. The first two authors are Joel Kastner and Rodolfo Montez Jr. of the Rochester Institute of Technology in New York, accompanied by 23 co-authors.
NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.
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Best image.
Posted by shak on Tuesday, 03.5.13 @ 12:50pm
Dear Esther,
Thanks for your suggestion on the names. The nebulas have official names and sometimes they have nicknames. We were not responsible for either.
-P. Edmonds, CXC
Posted by P. Edmonds on Friday, 11.9.12 @ 11:15am
To understand the properties of Supernova, one may need to understand the properties of Neutron matter and the various Quarks and axion matter that form a pasta. The electric-magnetic duality formed from such bulk ultra dense matter can explain the formation of the hour glass and bubble formations from droplets of condensed matter expanding.
The above explanation by Chandra is very elementary and needs the understanding of modern day astrophysics.
Posted by Harry Costas on Sunday, 10.28.12 @ 10:15am
I loved it. We have been studying this and we estimate various things using the studies of nature's laws. But how can we be so sure about the dance of nature in a particular manner or in accordance to laws? We can show that laws are just the illusion of no law nature. So, whatever NASA or any other scientific organization studies and estimates about anything in nature cannot come true. What if nature is random and has no law?
Posted by Dhiresh Yadav on Wednesday, 10.17.12 @ 06:39am
Your information is very important for me thank you...
Posted by mhamad saeid on Saturday, 10.13.12 @ 17:09pm
Maybe you should ask the public to name those nebula and than get a couple of poets to choose one. The one you call cat's eye is known as God's Eye. Please don't degrade these beautiful 'objects' by giving them these unimaginative names.
Posted by Esther Philips-Sweet on Friday, 10.12.12 @ 04:14am
Fantastic images, as if the star is to launch a net to capture his energy disperses over billions of years for a new beginning.
Very very wonderful.
Posted by carlos tatis on Wednesday, 10.10.12 @ 13:03pm