Starship Asterisk*

Borc wrote:Curious, this was a white dwarf that ate mass from a companion till it went boom. Isn't that a 1a supernova? Or a standard candle? Was it only brighter due to distance, or was it not 1a?

LocalColor wrote:This image looks like how my brain feels when I'm stressed...

The Dawg wrote:

LocalColor wrote:This image looks like how my brain feels when I'm stressed...

It reminds me of the space-brain through which Piccard drove the Enterprise, giving the space-brain persona a sort of massive migraine.

MargaritaMc wrote:

alter-ego wrote:This might be redundant, but I didn't see specific wavelength / energy clearly listed. To add some detail to the the above image link, I believe that red, green, and blue correspond to 0.5-0.8 keV (mostly, K lines of O), 0.8-2.0 keV (mostly, K lines of Ne, Mg, and Si), and 2.0-5.0 keV (mostly, synchrotron emission) bands. The middle-range wavelengths (in angstroms 1Å = 10^-10 meters) for these X-Ray energies are 19Å (red), 8.9Å ( green), and 3.5Å (blue).

Never having heard of K lines , I did a search and found this:

K-line (spectrometry)
The K-line is a spectral peak in astronomical spectrometry used, along with the L-line, to observe and describe the light spectrum stars.

The K-line is associated with iron (Fe), and is described as being from emissions at ~6.14keV (thousands of electron volts).
http://en.m.wikipedia.org/wiki/K-line_(spectrometry)

I am confused.
Well, MORE confused...

Margarita

rstevenson wrote: Astronomers have looked for a remnant star, which there would be if SN 1006 was the usual white-dwarf-companion-of-a-larger-star kind of explosion. But none have been found, so they conclude it likely happened through the merger of two white dwarfs. Such a merger would leave no remnant star, but it would still be a type 1a.

Rob

alter-ego wrote:

MargaritaMc wrote:

alter-ego wrote:This might be redundant, but I didn't see specific wavelength / energy clearly listed. To add some detail to the the above image link, I believe that red, green, and blue correspond to 0.5-0.8 keV (mostly, K lines of O), 0.8-2.0 keV (mostly, K lines of Ne, Mg, and Si), and 2.0-5.0 keV (mostly, synchrotron emission) bands. The middle-range wavelengths (in angstroms 1Å = 10^-10 meters) for these X-Ray energies are 19Å (red), 8.9Å ( green), and 3.5Å (blue).

Never having heard of K lines , I did a search and found this:

K-line (spectrometry)
The K-line is a spectral peak in astronomical spectrometry used, along with the L-line, to observe and describe the light spectrum stars.

The K-line is associated with iron (Fe), and is described as being from emissions at ~6.14keV (thousands of electron volts).
http://en.m.wikipedia.org/wiki/K-line_(spectrometry)

I am confused.
Well, MORE confused...

Margarita

Hi Margarita,
I'll try to simplify the perspective of the K-lines.
I think you know that atoms (elements) consist of nuclei "orbited" by electrons. Quantum physics describes these orbits (really energy levels) as having discrete values. If enough energy is transferred to an electron at one energy level, it will "jump" to another allowed level. When the excitation energy is high enough the electron is freed, and the atom is ionized. In the simple case, when an electron moves to another level, it (or another one) at that level jumps back to re-fill the empty energy level. When this happens energy is given off as electromagnetic radiation.

x-ray-emission.jpg

The graphic shows the allowed energy levels as orbital radii from the nucleus where the innermost orbital is known as the K-shell, then L-shell, etc. Note the arrows all point inward, and there is a set of "transition" arrows for each shell. Each arrow represents an electron jump to that orbital, and the longer the arrow, the higher the energy that's released during that transition. All transitions ending on a specific shell are given the name of that shell. So you can see set of longer arrows belong to the "K-lines", and consequently these lines generate the highest transition energies (X-rays). Now you can see that every element has a different set of shells, and therefore most elements have a set of K-lines (remember the energy levels we're discussing here are X-rays, not their lower-energy (visible) siblings.

I think this should help you understand K-lines. As a start, see: http://en.wikipedia.org/wiki/K-alpha
Of course, SN1006 is a very high-energy environment. X-rays are only part of the energy spectrum.

Hope this helps

http://wiki.answers.com/Q/Who_named_the_k_shell_orbit_and_why wrote:
Q: Why the shells of an orbit are named: K, L, M, N?

Answer: The names of the electron shells come from a fellow named Charles G. BarKLa, a spectroscopist who studied the X-rays that are emitted by atoms when they are hit with high energy electrons. He noticed that atoms appeared to emit two types of X-rays. The two types of X-rays differed in energy and BarKLa originally called the higher energy X-ray type A and the lower energy X-ray type B. He later renamed these two types K and L since he realized that the highest energy X-rays produced in his experiments might not be the highest energy X-ray possible. He wanted to make certain that there was room to add more discoveries without ending up with an alphabetical list of X-rays whose energies were mixed up. As it turns out, the K type X-ray is the highest energy X-ray an atom can emit. It is produced when an electron in the innermost shell is knocked free and then recaptured. This innermost shell is now called the K-shell, after the label used for the X-ray. BarKLa won the 1917 Nobel Prize for Physics for this work.

http://en.wikipedia.org/wiki/Barkla_%28crater%29 wrote:
<<BarKLa is a lunar impact crater that lies near the eastern limb of the Moon. It is located to the east of the prominent crater Langrenus, and was formerly designated Langrenus A before being renamed by the IAU. Due east of BarKLa is Kapteyn, a formation only slightly larger with a similar size. Southwest of BarKLa is the crater Lamé. The wall shows little appearance of erosion from subsequent impacts, and is not overlain by any craterlets of note.>>

http://en.wikipedia.org/wiki/K-alpha wrote:
<<An example of K-alpha lines are those seen for iron as iron atoms radiating X-rays spiralling into a black hole at the center of a galaxy. For such purposes, the energy of the line is adequately calculated to 2-digit accuracy by the use of Moseley's law. This formula is 10.2 eV multiplied by the square of a quantity one less than the atomic number of the element in question (atomic number minus 1). For example, K-alpha for iron (Z = 26) is calculated in this fashion as 10.2 eV (25)² = 6.38 keV energy. For astrophysical purposes, Doppler and other effects (such as gravitational broadening) show the iron line to no better accuracy than 6.4 keV.>>

neufer wrote: Material traveling 3% of the speed of light will hardly be affected by the gravity of stars that they pass.

However, stars close to the explosion with powerful magnetic fields and/or stellar winds might have an impact.

K1NS wrote:

neufer wrote:
Material traveling 3% of the speed of light will hardly be affected by the gravity of stars that they pass.

However, stars close to the explosion with powerful magnetic fields and/or stellar winds might have an impact.

Not true. For example, light travelling at 100% the speed of light is affected by the gravity of stars that it passes. (E.g., gravitational lensing.) Speed has little to do with it, except that the time the material is passing will be shorter at higher speed.

• Gravitational lensing involves tiny angles and vast distances.

K1NS wrote:
But we now know that the sphere of our Sun's heliopause is a significant proportion of a LY, so material passing by a star at 3% the speed of light will be passing for a long time, possibly years. Surely the bent paths of this material could cause the asymmetries noted in the photo.

• Don't confuse the heliopause with the Oort Cloud.