APOD: Halo of the Cat's Eye (2012 Aug 31)

[APOD Robot]

Halo of the Cat's Eye

Explanation: The Cat's Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its haunting symmetries are seen in the very central region of this tantalizing image, processed to reveal the enormous but extremely faint halo of gaseous material, about 6 light-years across, which surrounds the brighter, familiar planetary nebula. Made with narrow and broadband data the composite picture shows the remarkably strong extended emission from twice ionized oxygen atoms in blue-green hues and ionized hydrogen and nitrogen in red. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star. But recently many planetaries have been found to have halos like this one, likely formed of material shrugged off during earlier active episodes in the star's evolution. While the planetary nebula phase is thought to last for around 10,000 years, astronomers estimate the age of the outer filamentary portions of this halo to be 50,000 to 90,000 years.

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[Boomer12k]

Pretty picture!!!
Ann should be pleased...

Lots of wispy shapes.

AND IT IS MADE BY NIKE!!! (Nike symbol in Red, lower right...it is upside down.


:---[===] *

[Moonlady]

Totally beautiful!

[orin stepanek]

Pretty picture!!!
Ann should be pleased...

Lots of wispy shapes.

AND IT IS MADE BY NIKE!!! (Nike symbol in Red, lower right...it is upside down.


:---[===] *

Beautiful indeed; and it's Blue!

[starsurfer]

Mmmm......doubly ionized oxygen! Is one of the most detailed images of this planetary nebula. There should be at least 2-5 more planetary nebula images per year on APOD! Stardeath is beautiful!!

[Devil Particle]

It appears to be hexagonal in shape. Is there any known reason for this and could it be linked to Saturn's hexagonal south polar vortex?

[neufer]

It appears to be hexagonal in shape.

Is there any known reason for this and could it be linked to Saturn's hexagonal south polar vortex?

It has nothing to do with Saturn's hexagonal south polar vortex.

It is probably some sort of extension of the inner symmetries:
http://apod.nasa.gov/apod/ap110424.html

[AlfaCentaury]

beautiful picture !

[Psnarf]

Is it possible that the structure of the halo results from the central star's ancient stellar wind interacting with the magnetic pressure of the interstellar medium, much like our own heliosphere?
[Idle speculation.]

http://www.nasa.gov/mission_pages/ibex/ ... shock.html
http://swri.org/9what/releases/2012/bowshock.htm
http://www.spacetelescope.org/videos/heic0414a

[LocalColor]

Absolutely beautiful. The Cat's Eye is one of my favorites.

[Ann]

Pretty picture!!!
Ann should be pleased...

Lots of wispy shapes.

AND IT IS MADE BY NIKE!!! (Nike symbol in Red, lower right...it is upside down.


:---[===] *

Beautiful indeed; and it's Blue!

Indeed, it's beautiful!

Ann

[neufer]

Halo of the Cat's Eye

The largest crater is approx. 60 km in diameter

Cat's Eye: Messenger, Aug. 30, 2012

<<This crater, located on the eastern margin of [Mercury's] Rembrandt basin, has a distinctive, elongate depression oriented north-south on its floor. The depression was previously imaged in mosaics of Rembrandt (it is barely visible near the center of this color image), and morphologically resembles depressions interpreted as volcanic vents elsewhere on Mercury. That this vent is aligned with where we would expect Rembrandt's rim to lie (were it not removed by this crater) suggests that the larger basin may have structurally controlled the location and development of this pit.

This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.>>

Credit: NASA/JHU APL/CIS

[neufer]

[b][color=#0000FF]Adah takes a lick of Richie Townsend’s telescope mirror during its final rinse. Credit: Richie Townsend[/color][/b]

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Adah the cat caught licking the looking glass
Posted on September 3, 2012 by astrobob

<<This sweet photo makes me cringe and laugh at the same time. Amateur astronomer Richie Townsend of Duluth, Minn. was cleaning his 8-inch telescope mirror when his cat Adah walked up, saw her reflection and started licking away. Look closely and you’ll see a water film on the mirror. How could she resist a few licks off that silvery surface? “I was nearly finished with the final rinse,” said Townsend. “Her “help” only required a small extra swipe with a cloth.”

Telescope mirror surfaces are ground to an accuracy of about one-millionth of an inch and coated on their front surface by a thin film of highly-reflective aluminum. They’re different from everyday mirrors, which are coated on the backside. Good thing. If a bathroom mirror were aluminized on the front side, you’d soon damage the coating after a few cleanings with Windex. Astronomical mirrors are coated on the front side to prevent precious light rays from being absorbed by a layer of glass. Aluminum coatings are still soft and vulnerable to scratching during the occasional cleanings they require. That’s why telescope mirror manufactures apply an additional overcoat of transparent silicon dioxide (silica). Silica is commonly found in nature as sand and quartz. The overcoat is tough enough to allow for gentle, infrequent cleanings.

A friend pointed out it was a good thing Adah didn’t cough up a hairball. Good thing indeed. Acids and salts can slowly eat away at mirror coatings. You might be surprised (or not) to know that acid, as in acid rain, is also found in dew. Repeating dewings of telescope mirrors on damp nights will slowly etch and flake coatings. Salty air near the oceans is no friend of mirrors either. It costs about $70 to re-coat a typical 8-inch telescope mirror. That’s why amateur and professional astronomers alike baby their mirrors, trying to find a balance between overcleaning and keeping them dew-free. I’ve got a low-wattage light bulb rigged up under my main telescope mirror to keep it warm overnight so no dew can form. I unplug the light and let the mirror cool down before using the scope at night.>>

[Devil Particle]

It appears to be hexagonal in shape.

Is there any known reason for this and could it be linked to Saturn's hexagonal south polar vortex?

It has nothing to do with Saturn's hexagonal south polar vortex.

It is probably some sort of extension of the inner symmetries:
http://apod.nasa.gov/apod/ap110424.html

Maybe it has something to do with the presence of water crystals.

[neufer]

It appears to be hexagonal in shape.

Is there any known reason for this and could it be linked to Saturn's hexagonal south polar vortex?

It has nothing to do with Saturn's hexagonal south polar vortex.

It is probably some sort of extension of the inner symmetries:
http://apod.nasa.gov/apod/ap110424.html

Maybe it has something to do with the presence of water crystals.

It has nothing to do with the presence of any water crystals.