Astronomy Picture of the Day 9-04-02

NASA ^ | 9-04-02 | Robert Nemiroff and Jerry Bonnell

[petuniasevan]

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2002 September 4

Halo of the Cat's Eye
Credit: R. Corradi (Isaac Newton Group), D. Goncalves (Inst. Astrofisica de Canarias)

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 stunning false-color picture, processed to reveal the enormous but extremely faint halo of gaseous material, over three light-years across, which surrounds the brighter, familiar planetary nebula. Made with data from the Nordic Optical Telescope in the Canary Islands, the composite picture shows emission from nitrogen atoms as red and oxygen atoms as green and blue shades. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star. Only much more recently however, have some planetaries 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.

[petuniasevan]

Astronomy Fun Fact:

Stars all eventually run out of hydrogen for fusion. A star's mass determines its fate. A star with the sun's mass (or a bit more, according to some researchers) will first become a red giant, then shed the outer layers into space to create a beautiful grave marker, as it were: a planetary nebula. Eventually only the core remains as a slowly cooling white dwarf.

Compare the above image with the APOD HST image of the central region.

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[petuniasevan]

[BossyRoofer]

Pictures like this is why APOD is my favorite site!

[mtngrl@vrwc]

Pictures like this is why APOD is my favorite site!

Amen to that! What a breathtaking picture!

[sleavelessinseattle]

AI CARUMBA!!!Everybody gets a ping on this one and All my non FReeper buds as well! NICE ONE, Creatrix!!!;-D Covering the bases!

[Libertina]

Thanks for the ping! Amazing photo.

[2Trievers]

"NICE ONE, Creatrix"

WTG Sleavester ... glad you know which side your moon is cheesed on ... or was that buttered on? Well you get my drift ... er, orbit ... oh, "WHATEVER"! &;-)

[colorado tanker]

Thanks for the ping. Absolutely stunning!

[sleavelessinseattle]

"NICE ONE, Creatrix"

Well, After I found out the universe was not only expanding, but Accelerating in its expansion...I figure...Vacuum energy retention...Sic Transit!

[PsyOp]

Very Cool Bump. Thank you Supreme Leader!

[2Trievers]

Maybe you'd like to see my new Fusion Plasma Simulation Laboratory that has been specially designed for studies of hydrogen/deuterium permeation and retention in materials and materials erosion due to hydrogenic particle impact. Diagnostics include quadrupole mass spectrometers, residual gas analyzers, ionization gauges, Auger electron spectrometer for surface analysis, and a Laser-Thermal-Desorption apparatus for H/D retention measurements. The interaction of tritium (radioactive fusion fuel) with reactor materials is my next project to study in the new Low Level Tritium Lab.

The ultrahigh vacuum system unit still needs tweaking though, it seems the electron beams and low-energy-high-flux ion accelerators (H+, D+, He+, O+, C+, Nc+, Ar+ ions) are not putting out the readings I expected. Gotta get back to work after I pick up some tokamak codeposits for experiment. TTYL &;-)

[petuniasevan]

Gotta have a big backyard for that puppy!

The neighbors must love your project.

Can you modify the system to allow the interaction of Gephardt and Daschle with reactor materials?

[2Trievers]

Molecules travel on ballistic trajectories

• In a collisionless atmosphere, energy is still partitioned between thermal (kinetic) energy and gravitational (potential) energy
• Now H is simply the height of a typical bounce of a single molecule:

  kT = mgH --> H = kT/mg where

  • m = mass of a molecule (kg) Lieberman
  • T = temperature Dodd
  • k = Boltzmann constant (1.381 x 10^-23 J/K) Daschle
  • g = gravitational constant (9.8 J/m/kg) Gephardt

  It is the "characteristic height" of democratic atmospheric molecules determined by a balance between their thermal energy and gravitational potential energy that leads me to the conclusion that these constiuents are not shielded from solar wind, UV, X-rays, or cosmic rays.

  In other words, these blowhards need contant refreshing of their hyperbolic or parabolic characteristics. &;-)

[sleavelessinseattle]

I can't believe you're still using a magnetic Torus to contain your Energized hydrogen Plasma! Laser detonated Deuterium Pellets are literally the BOMB, Baby! And as to your Laser Thermal Deuterium Desorption?...I just wear wool socks...keeps my feet warm regardless of how much heavy water I'm wading in!

I hear your house is as hot as a plutonium breeder reactor!;-) Perhaps some quakeresque house rules?

[PsyOp]

"Gotta get back to work after I pick up some tokamak codeposits for experiment."

I thought you were an art major? 8-]

[PsyOp]

"* Now H is simply the height of a typical bounce of a single molecule:"

I myself have been contemplating a series of kinetic-energy experiments in which I hope to measure the typical number of bounces produced by democrat body impacting concrete from various distances under conditions of extreme gravity. I've yet to find a sufficiently dense gravity well yet - but I'm still looking. Leahey seems a prime candidate, but I'm afraid the lack of noble gas atmosphere may skew the results.

Any thoughts?

[sleavelessinseattle]

Re the kinetic energy experiments...Whenever I think of Democrats...I'm reminded of the time that British Airways borrowed the compressed air Chicken Corpse cannon that Boeing uses to test windshields for resistance to birdstrikes and they were embarassed at the results they got until they mentioned the problem to Boeing and The Lazy B responded...You might try letting the Dead Birds THAW before launching them at the windshield! I'm not persuaded that The Demo's would be worth waiting for full ambient temp chickens....

[2Trievers]

"I thought you were an art major?"

Yep ... lots of minors ... with a few Majors thrown in ... a few more degrees ... who's counting? &;-)

[2Trievers]

According to my algore-ithm calculations, Leaheithm (n: lea-he-ith-m): Any method of calculation performed repeatedly until a prior desired result is produced ... maybe we can compute a method for his ouster using the formula above and multiply both sides by N (Avogadro's Number) and use the relationship

R = kN

to get:

H = RT/µg

[PsyOp]

At what point in the gravity coefficient does 'bounce' revert to its inverse and become 'splat'? And is that a function of velocity or mass?

P.S. I never did well with algebraic equations, but this seems to be working for me. Certainly I would have done much better under your tutelage. ;-]