Pic Of The Day 30th March

Soldato
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Todays pic is another one that is done for just the sheer beauty and the wow effect caused when first viewing it.:)

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Hubble Probes the Complex History of a Dying Star

This NASA Hubble Space Telescope image shows one of the most complex planetary nebulae ever seen, NGC 6543, nicknamed the "Cat's Eye Nebula." Hubble reveals surprisingly intricate structures including concentric gas shells, jets of high-speed gas and unusual shock-induced knots of gas. Estimated to be 1,000 years old, the nebula is a visual "fossil record" of the dynamics and late evolution of a dying star.

A preliminary interpretation suggests that the star might be a double-star system. The dynamical effects of two stars orbiting one another most easily explains the intricate structures, which are much more complicated than features seen in most planetary nebulae. (The two stars are too close together to be individually resolved by Hubble, and instead, appear as a single point of light at the center of the nebula.)

According to this model, a fast "stellar wind" of gas blown off the central star created the elongated shell of dense, glowing gas. This structure is embedded inside two larger lobes of gas blown off the star at an earlier phase. These lobes are "pinched" by a ring of denser gas, presumably ejected along the orbital plane of the binary companion.

The suspected companion star also might be responsible for a pair of high- speed jets of gas that lie at right angles to this equatorial ring. If the companion were pulling in material from a neighboring star, jets escaping along the companion's rotation axis could be produced.

These jets would explain several puzzling features along the periphery of the gas lobes. Like a stream of water hitting a sand pile, the jets compress gas ahead of them, creating the "curlicue" features and bright arcs near the outer edge of the lobes. The twin jets are now pointing in different directions than these features. This suggests the jets are wobbling, or precessing, and turning on and off episodically.

This color picture, taken with the Wide Field Planetary Camera-2, is a composite of three images taken at different wavelengths. (red, hydrogen-alpha; blue, neutral oxygen, 6300 angstroms; green, ionized nitrogen, 6584 angstroms). The image was taken on September 18, 1994. NGC 6543 is 3,000 light-years away in the northern constellation Draco.

The term planetary nebula is a misnomer; dying stars create these cocoons when they lose outer layers of gas. The process has nothing to do with planet formation, which is predicted to happen early in a star's life.

This material was presented at the 185th meeting of the American Astronomical Society in Tucson, AZ on January 11, 1995.

Credit: J.P. Harrington and K.J. Borkowski (University of Maryland), and NASA


A larger version of this piccy can be found here, this is a 1.83MB Tiff image.

Previous Pic Of The Day posts

28th Mar 03
26th Mar 03
22nd Mar 03
21st Mar 03
20th Mar 03
19th Mar 03Courtesy of Mark G
18th Mar 03
 
Associate
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very nice, I wish we could have one of these happen a bit nearer to us so we could have a look with with our binoculars. I guess it would be worth wearing the aluminium visor to protect from all the cosmic rays etc..;)
 
Soldato
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Originally posted by Qball
Hey great pic man! Has there been any more planets found that you know about?

TBH, planetary stuff has never interested me much, but since you have asked it's a case of watch this space, I think I've found a topic for a future pic of the day.:)
 
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