APOD: Kepler's Supernova Remnant in X Rays (2013 May 15)

[APOD Robot]

Kepler's Supernova Remnant in X Rays

Explanation: What caused this mess? Some type of star exploded to create the unusually shaped nebula known as Kepler's supernova remnant, but which type? Light from the stellar explosion that created this energized cosmic cloud was first seen on planet Earth in October 1604, a mere four hundred years ago. The supernova produced a bright new star in early 17th century skies within the constellation Ophiuchus. It was studied by astronomer Johannes Kepler and his contemporaries, without the benefit of a telescope, as they searched for an explanation of the heavenly apparition. Armed with a modern understanding of stellar evolution, early 21st century astronomers continue to explore the expanding debris cloud, but can now use orbiting space telescopes to survey Kepler's supernova remnant (SNR) across the spectrum. Recent X-ray data and images of Kepler's supernova remnant taken by the orbiting Chandra X-ray Observatory has shown relative elemental abundances typical of a Type Ia supernova, and further indicated that the progenitor was a white dwarf star that exploded when it accreted too much material from a companion Red Giant star and went over Chandrasekhar's limit. About 13,000 light years away, Kepler's supernova represents the most recent stellar explosion seen to occur within our Milky Way galaxy.

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[bystander]

http://asterisk.apod.com/viewtopic.php?t=30971

[Boomer12k]

Interesting how we use different wavelengths of energy to discern what is going on, and not just with stars, but Nebula as well.
QUESTION:...What does it do to the Red Giant?????

Reminds me of the Space Amoeba episode of Star Trek...

:---[===] *

[neufer]

[b][size=150][color=#0000FF]Stanczyk thinks about the Polish Gordian Knot [/color][/size][/b] [url=http://www.mit.edu/~kardar/research/seminars/knots/art/KnotsinArt.html][size=150]Knots in Art by Piotr Pieranski[/size][/url]

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<<The Gordian Knot is a legend of Phrygian Gordium associated with Alexander the Great. It is often used as a metaphor for an intractable problem (disentangling an "impossible" knot) solved easily by cheating or "thinking outside the box [vs. Googling]" ("cutting the Gordian knot"):

• King Henry V Act 1, Scene 1

CANTERBURY: Turn him to any cause of policy,

• The Gordian knot of it he will unloose,

• Cymbeline Act 2, Scene 2

IACHIMO: Come off, come off: [Taking off her bracelet]

• As slippery as the Gordian knot was hard!

At one time the Phrygians were without a king. An oracle at Telmissus (the ancient capital of Phrygia) decreed that the next man to enter the city driving an ox-cart should become their king. A peasant farmer named Gordias drove into town on an ox-cart. His position had also been predicted earlier by an eagle landing on his cart, a sign to him from the gods, and, on entering the city, Gordias was declared king by the priests. Out of gratitude, his son Midas dedicated the ox-cart to the Phrygian god Sabazios (whom the Greeks identified with Zeus) and either tied it to a post or tied its shaft with an intricate knot of cornel (Cornus mas) bark. The ox-cart still stood in the palace of the former kings of Phrygia at Gordium in the fourth century BC when Alexander arrived, at which point Phrygia had been reduced to a satrapy, or province, of the Persian Empire.

Several themes of myth converged on the chariot, as Robin Lane Fox remarks: Midas was connected in legend with Alexander's native Macedonia, where the lowland "Gardens of Midas" still bore his name, and the Phrygian tribes were rightly remembered as having once dwelt in Macedonia. So, in 333 BC, while wintering at Gordium, Alexander the Great attempted to untie the knot. When he could not find the end to the knot to unbind it, he sliced it in half with a stroke of his sword, producing the required ends (the so-called "Alexandrian solution"). That night there was a violent thunderstorm. Alexander's prophet Aristander took this as a sign that Zeus was pleased and would grant Alexander many victories. Once Alexander had sliced the knot with a sword-stroke, his biographers claimed in retrospect that an oracle further prophesied that the one to untie the knot would become the king of Asia.

Interpretations: The knot may have been a religious knot-cipher guarded by Gordian/Midas's priests and priestesses. Robert Graves suggested that it may have symbolized the ineffable name of Dionysus that, knotted like a cipher, would have been passed on through generations of priests and revealed only to the kings of Phrygia.>>

[Chris Peterson]

Interesting how we use different wavelengths of energy to discern what is going on, and not just with stars, but Nebula as well.

It's interesting that we can, but not so much that we do. After all, this is no different than our using our eyes and sense of color to observe the world around us. We're just using instruments to extend the range of colors we can see.

QUESTION:...What does it do to the Red Giant?????

Some of the red giant's atmosphere would probably be stripped away, but for the most part, the star should survive. It would, however, have its orbit substantially changed- probably into a hyperbolic orbit with respect to the progenitor, meaning that it gets ejected from the system.

[neufer]

[url=http://nssdc.gsfc.nasa.gov/astro/astrolist.html][size=150][b]Space observatories and their working ranges[/b][/size][/url]

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Interesting how we use different wavelengths of energy to discern what is going on, and not just with stars, but Nebula as well.

It's interesting that we can, but not so much that we do. After all, this is no different than our using our eyes and sense of color to observe the world around us. We're just using instruments to extend the range of colors we can see.

~1 octave => ~60 octaves
LOFAR => 30 x 10⁹ nm
AGILE => 25 x 10^-9 nm

QUESTION:...What does it do to the Red Giant?????

Some of the red giant's atmosphere would probably be stripped away, but for the most part, the star should survive. It would, however, have its orbit substantially changed- probably into a hyperbolic orbit with respect to the progenitor, meaning that it gets ejected from the system.

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[K1NS]

This photo reminds me very much of a video posted on Science Friday http://www.sciencefriday.com/segment/03 ... knots.html this last March. Physicists at the University of Chicago were able to tie water currents into a knotted vortex that looks very much like the Kepler's remnant.

Do the same physics apply?

[neufer]

This photo reminds me very much of a video posted on Science Friday http://www.sciencefriday.com/segment/03 ... knots.html this last March. Physicists at the University of Chicago were able to tie water currents into a knotted vortex that looks very much like the Kepler's remnant.

Do the same physics apply?

• It's a mystery
  
  • Hamlet, Prince of Denmark Act 1, Scene 5
  Ghost: Make thy two eyes, like stars, start from their spheres,
  • Thy knotted and combined locks to part
    And each particular hair to stand on end,
    Like quills upon the fretful porpentine:
  • Love's Labour's Lost Act 1, Scene 1
  FERDINAND: Now for the ground which; which,
  • I mean, I walked upon: it is y-cleped thy park. Then
    for the place where; where, I mean, I did encounter
    that obscene and preposterous event, that draweth
    from my snow-white pen the ebon-coloured ink, which
    here thou viewest, beholdest, surveyest, or seest;
    but to the place where; it standeth north-north-east
    and by east from the west corner of thy curious-
    knotted garden: there did I see that low-spirited
    swain, that base minnow of thy mirth,'--

<<The early, significant stimulus in knot theory would arrive with Sir William Thomson (Lord Kelvin) and his theory of vortex atoms.

In 1867 after observing Scottish physicist Peter Tait's experiments involving smoke rings, Thomson came to the idea that atoms were knots of swirling vortices in the æther. Chemical elements would thus correspond to knots and links. Tait's experiments were inspired by a paper of Helmholtz's on vortex-rings in incompressible fluids. Thomson and Tait believed that an understanding and classification of all possible knots would explain why atoms absorb and emit light at only the discrete wavelengths that they do. For example, Thomson thought that sodium could be the Hopf link due to its two lines of spectra. Tait subsequently began listing unique knots in the belief that he was creating a table of elements. He formulated what are now known as the Tait conjectures on alternating knots. (The conjectures were proved in the 1990s.) Tait's knot tables were subsequently improved upon by C. N. Little and Thomas Kirkman.

James Clerk Maxwell, a colleague and friend of Thomson's and Tait's, also developed a strong interest in knots. Maxwell studied Listing's work on knots. He re-interpreted Gauss' linking integral in terms of electromagnetic theory. In his formulation, the integral represented the work done by a charged particle moving along one component of the link under the influence of the magnetic field generated by an electric current along the other component. Maxwell also continued the study of smoke rings by considering three interacting rings.

When the luminiferous æther was not detected in the Michelson–Morley experiment, vortex theory became completely obsolete, and knot theory ceased to be of great scientific interest. Modern physics demonstrates that the discrete wavelengths depend on quantum energy levels.>>

[mjimih]

it appears to have a coil shape to it. Is that a real perception, or imagined?

Mark

[retrogalax]

Hi,

This shape looks a bit like the famous Helix Nebula to me or Cat's Eyes Nebula also, a shape named "prolate spheroid" (wikipedia).
Maybe it could be a superposition of many rings; but it would be a too simple description.