Wavelengths in recent M flare (2021-10-09 06:40) are oddly specific to iron, how could this be?

[HalfFeralHuman]

I noticed something that seems a little odd to me about this recent flare when looking at the SDO's imagery. The brightest flash of the flare produced that X shaped refraction pattern, but only on the channels 094, 131 and 335 angstroms and not others.

These wavelengths correspond with iron 18, iron 20&23 and iron 16 respectively. I'm thinking that this intensity being specific to these wavelengths would indicate iron fusion, but if I'm not misunderstanding things, our sun isn't close to being capable of that.

Is it possible that certain conditions, perhaps extremely condensed magnetic fields reconfiguring, could create a localised phenomenon capable of iron fusion?

SDO link for convenience

[Newbie]

Hello HalfFeralHuman:

Firstly I don't believe Iron fusion is taking place on the Sun. Once a star arrives at the point of Iron fusion, it has exhausted it's supply of all other fuel and the fusion process ceases. As Iron atoms are bound so closely together the energy spent in their fusion is so great that the core cools, resulting in stellar death

The SDO observes many different wavelengths from the Sun's surface and outwards. Specifically 335Aº (Angstroms) shows hotter, magnetically active regions in the corona, 131Aº - hottest material in a flare and 94Aº - highlights regions of the corona during a solar flare.

Nonetheless it was exciting to see an M-flare yesterday from a region that didn't appear to be that active.

Newbie

Edit:

I’m not sure what you mean by the numbers 16, 18, 20 & 23. Were you referring to spectral lines for Iron? I’m not sure about the units you are using.

No matter 😀

 

Edited October 10, 2021 by Newbie

[Marcel de Bont]

In all honesty, you're question should be aimed to someone like Dr. K Strong, a retired solar physicist. The X shape is caused by the lenses or filters inside the SDO/AIA array and is thus a side effect, not some shape actually happening on the Sun in case you wondered.

[HalfFeralHuman]

Quote

I’m not sure what you mean by the numbers 16, 18, 20 & 23. Were you referring to spectral lines for Iron? I’m not sure about the units you are using.

Sorry, those numbers are ionization states. They'd usually be written as Fe XVI, etc. but I've seen them written as iron-16 or just iron 16, which i guess is kinda easy to confuse with nuclides, especially given the context.

 

I did some digging and I guess I've answered my own question:

There is a fair bit of iron and other heavier stuff in the sun and it's corona anyway and this has been known for a while. Some of the wavelengths used by the SDO are deliberately chosen to match up to these various highly ionised iron ions' spectral lines (that's a phrase and a half 😛). The level of ionisation of iron in the corona tells us a lot about it's heat. The observation I came in with could be just down to the heat levels.

I realised that there was a rather a large assumption in my question - that the presence of iron in and around the sun means the sun is making it. The general consensus is that these heavier elements most likely came from elsewhere and aren't made by the sun. Certainly as said if the sun was fusing any significant quantities of iron, a lot of people would be very worried and would certainly be talking about it (assuming anyone was alive to talk about it).

 

I do reckon that there's still a possibility that a magnetic reconnection event could potentially create a moment of highly localised magnetic flux powerful enough to shoot all the electrons of various elements in one direction and the remaining ionised nuclei in the other at extreme velocities. The velocity that any particular nucleus would be fired at by the impulse would depend on the nucleus's mass:charge ratio, and thus they would end up grouped by type in a manner analogous to fractional distillation. I'm thinking this could potentially create conditions enabling the fusion of heavier elements, albeit only very briefly.

From what I can tell I'm not the only one who's thought something along these lines, but there'd be no way to know at the moment. Perhaps when the Parker probe gets closer it'll tell us something interesting. I think it'd be an a really interesting alternative explanation for the presence of heavier elements in the sun if the theory carries any weight, as it could offer an explanation for other cosmic overabundances of heavy elements.

@Marcel de Bont

Thanks, that looks like an interesting channel.

Yeah, I figured the X shapes were a camera artefact. I'd noticed that they only show up on very bright flares, so I figure they make a good indication of extreme intensity on a given band.

[Newbie]

20 hours ago, HalfFeralHuman said:

Sorry, those numbers are ionization states. They'd usually be written as Fe XVI, etc. but I've seen them written as iron-16 or just iron 16, which i guess is kinda easy to confuse with nuclides, especially given the context.

 

I did some digging and I guess I've answered my own question:

There is a fair bit of iron and other heavier stuff in the sun and it's corona anyway and this has been known for a while. Some of the wavelengths used by the SDO are deliberately chosen to match up to these various highly ionised iron ions' spectral lines (that's a phrase and a half 😛). The level of ionisation of iron in the corona tells us a lot about it's heat. The observation I came in with could be just down to the heat levels.

I realised that there was a rather a large assumption in my question - that the presence of iron in and around the sun means the sun is making it. The general consensus is that these heavier elements most likely came from elsewhere and aren't made by the sun. Certainly as said if the sun was fusing any significant quantities of iron, a lot of people would be very worried and would certainly be talking about it (assuming anyone was alive to talk about it).

 

I do reckon that there's still a possibility that a magnetic reconnection event could potentially create a moment of highly localised magnetic flux powerful enough to shoot all the electrons of various elements in one direction and the remaining ionised nuclei in the other at extreme velocities. The velocity that any particular nucleus would be fired at by the impulse would depend on the nucleus's mass:charge ratio, and thus they would end up grouped by type in a manner analogous to fractional distillation. I'm thinking this could potentially create conditions enabling the fusion of heavier elements, albeit only very briefly.

From what I can tell I'm not the only one who's thought something along these lines, but there'd be no way to know at the moment. Perhaps when the Parker probe gets closer it'll tell us something interesting. I think it'd be an a really interesting alternative explanation for the presence of heavier elements in the sun if the theory carries any weight, as it could offer an explanation for other cosmic overabundances of heavy elements.

 

Yes I was thinking it might be ionisation due to heat! 

A quick Google search says it takes 3 billion degrees for Iron fusion, or at least Silicon fusion, to produce Iron. 

The 10 million plus degrees that produces iron 20 and iron 23 is still way short of that figure. It's mind boggling that the Sun's corona gets that hot and it is still not understood how.

The pressure is only about 0.1  -  0.6 Pa in the active regions of the Sun's corona, being mainly gaseous. I would think that Iron fusion would occur under much greater pressures.

Anyway, I found this on a NASA site,  you've probably already seen it. 

From the sun's surface on out, the wavelengths SDO observes, measured in Angstroms, are:

4500: White light continuum, shows the sun's surface or photosphere

1700: Ultraviolet light continuum, shows surface of the sun. As well as a layer of the sun's atmosphere called the chromosphere, which lies just above the photosphere and is where the temperature begins rising.

1600: Emitted by carbon-4 (C IV) at around 10,000 Kelvin. C IV at these temperatures is present in the upper photosphere and what's called the transition region, a region between the chromosphere and the upper most layer of the sun's atmosphere called the corona. The transition region is where the temperature rapidly rises. SDO images of this wavelength are typically colorized in dark yellow.

304: Emitted by helium-2 (He II) at around 50,000 Kelvin. This light is emitted from the chromosphere and transition region. SDO images of this wavelength are typically colorized in red.

171: Emitted by iron-9 (Fe IX) at around 600,000 Kelvin. This wavelength shows the quiet corona and coronal loops, and is typically colorized in gold.

193: Emitted by iron-12 (Fe XII) at 1,000,000 Kelvin and iron 24 (Fe XXIV) at 20,000,000 Kelvin. The former represents a slightly hotter region of the corona and the later represents the much hotter material of a solar flare. This wavelength is typically colorized in yellow.

211: Emitted by iron-14 (Fe XIV) at temperatures of 2,000,000 Kelvin. These images show hotter, magnetically active regions in the sun's corona and are typically colorized in purple.

335: Emitted by iron-16 (Fe XVI) at temperatures of 2,500,000 Kelvin. These images also show hotter, magnetically active regions in the corona, and are typically colorized in blue.

94: Emitted by iron-18 (Fe XVIII) at temperatures of 6,000,000 Kelvin. Temperatures like this represent regions of the corona during a solar flare. The images are typically colorized in green.

131: Emitted by iron-20 (Fe XX) and iron-23 (Fe XXIII) at temperatures greater than 10,000,000 Kelvin, representing the material in flares. The images are typically colorized in teal.

Courtesy SDO/ NASA/ et al.

Newbie

 

 

Edited October 11, 2021 by Newbie

[HalfFeralHuman]

@Newbie Thanks for putting the specific info here. I'll mark yours as the solution as it seems to give a more detailed answer to the original question without the far-reaching hypothesising 😛.

I guess it's better to assume that iron fusion is indeed impossible at any scale on the sun, but...... ....

----------

Alert - More random, unprovable and possibly improbable hypothesising incoming, I just can't quite resist debating the possibility. Just in case it isn't really obvious, I'm not a nuclear physicist (or any kind of physicist) and I could well be talking complete rubbish. I just like debating these kinds of things to better understand stuffs.

I'm thinking the the 3 billion Kelvin, requirement for fusion isn't necessarily a total show stopper for this idea. I've got few thoughts here:

So in talking about temperature, we're talking about the average speed of particles in a high entropy system factored with pressure. With fusion we're talking about the energy required in a collision between nuclei for fusion to happen. Here's where the relationship between moving charged stuff and magnetic fields comes into play. In this hypothetical scenario, these nuclei are going to be both extremely charged and moving at extreme velocities through a very strong magnetic field. They'll start moving in a spiral (or circular if tangential) motion. The motion of these very fast charged nuclei will also generate their own local magnetic fields (back-EMF), which would be relevantly strong due to their velocity. We'd potentially end up with an extremely complicated system of electromagnetic forces, those of these local fields reconfiguring chaotically and those of the electric repulsion of the charged particles. As the entropy of this system increases and the relative motion of the particles become more chaotic, I'm thinking we could well end up with the occasional inter-nuclei collision with enough energy to cause them to fuse. Essentially, the energy which initially accelerated these particles has been converted to the temperature needed in an extremely localised zone. I'd also predict a bow-shock compressing things as the net velocity decreases, further increasing temperature. Fusion of smaller-than-iron elements could also generate more heat in a chain-reaction that would continue until we ended with mostly iron or the system dispersed, which I'd expect to happen extremely quickly due to both temperature and electrostatic repulsion.

While I believe such a thing should be possible, this is of course all idle hypothesis and could be riddled with erroneous thinking. Even if I'm right here, It's certainly not something that predicts anything dramatic.

[Newbie]

16 hours ago, HalfFeralHuman said:

@Newbie Thanks for putting the specific info here. I'll mark yours as the solution as it seems to give a more detailed answer to the original question without the far-reaching hypothesising 😛.

I guess it's better to assume that iron fusion is indeed impossible at any scale on the sun, but...... ....

----------

Alert - More random, unprovable and possibly improbable hypothesising incoming, I just can't quite resist debating the possibility. Just in case it isn't really obvious, I'm not a nuclear physicist (or any kind of physicist) and I could well be talking complete rubbish. I just like debating these kinds of things to better understand stuffs.

I'm thinking the the 3 billion Kelvin, requirement for fusion isn't necessarily a total show stopper for this idea. I've got few thoughts here:

So in talking about temperature, we're talking about the average speed of particles in a high entropy system factored with pressure. With fusion we're talking about the energy required in a collision between nuclei for fusion to happen. Here's where the relationship between moving charged stuff and magnetic fields comes into play. In this hypothetical scenario, these nuclei are going to be both extremely charged and moving at extreme velocities through a very strong magnetic field. They'll start moving in a spiral (or circular if tangential) motion. The motion of these very fast charged nuclei will also generate their own local magnetic fields (back-EMF), which would be relevantly strong due to their velocity. We'd potentially end up with an extremely complicated system of electromagnetic forces, those of these local fields reconfiguring chaotically and those of the electric repulsion of the charged particles. As the entropy of this system increases and the relative motion of the particles become more chaotic, I'm thinking we could well end up with the occasional inter-nuclei collision with enough energy to cause them to fuse. Essentially, the energy which initially accelerated these particles has been converted to the temperature needed in an extremely localised zone. I'd also predict a bow-shock compressing things as the net velocity decreases, further increasing temperature. Fusion of smaller-than-iron elements could also generate more heat in a chain-reaction that would continue until we ended with mostly iron or the system dispersed, which I'd expect to happen extremely quickly due to both temperature and electrostatic repulsion.

While I believe such a thing should be possible, this is of course all idle hypothesis and could be riddled with erroneous thinking. Even if I'm right here, It's certainly not something that predicts anything dramatic.

 

In the nineteenth century, scientists observed a spectral line at 530.3 nanometers in the Sun’s outer atmosphere, the corona. This line had never been seen before, an assumption was made that this line was the result of a new element found in the corona, and it was named coronium. It was not until 60 years later that astronomers discovered that this emission was in fact due to highly ionized iron - iron with 13 of its electrons stripped off. This is how it was first discovered that the Sun’s atmosphere had a temperature of more than a million degrees.

In the Sun's corona the no. of atoms of iron is around 0.003% of total atoms and the mass of iron makes up about 0.14% of total mass. IMO there is not enough iron present for fusion to occur even without considering temperatures and pressures.

In very large stars as fuel runs out, fusion will not continue because the amount of energy required to fuse iron, an endothermic reaction, results in overall cooling and ultimately stellar death.

From what I have read, only in a supernova will you find enough energy to fuse iron into heavier elements.

Newbie

[HalfFeralHuman]

@Newbie

I guess this is exactly what I'm challenging. Of course this is all really hypothetical but I'm suggesting there might be a scenario where the concentration and other conditions at a point, rather than the looking at the sun as a whole, may make this possible.

There is this unanswered question as to the overabundance of heavy elements. I guess I'm just putting out a very tentative hypothesis as to why. But... we're in the 'who the f## knows' territory anyway, so perhaps this is better considered as philosophy than science. To me, the one leads to the other, but I'm certain that's a contentious point.

Edited October 12, 2021 by HalfFeralHuman
clarification

[Newbie]

1 hour ago, HalfFeralHuman said:

@Newbie

I guess this is exactly what I'm challenging. Of course this is all really hypothetical but I'm suggesting there might be a scenario where the concentration and other conditions at a point, rather than the looking at the sun as a whole, may make this possible.

There is this unanswered question as to the overabundance of heavy elements. I guess I'm just putting out a very tentative hypothesis as to why. But... we're in the 'who the f## knows' territory anyway, so perhaps this is better considered as philosophy than science. To me, the one leads to the other, but I'm certain that's a contentious point.

HFH: I hope you don't mind the abbreviation of your name.

I understand where you are coming from with regards to observations taken at the atomic or even quantum level and what might be happening. I did consider it. The conditions that are able to be produced in the LHC (Large Hadron Collider) at this point in time are nowhere near what is required to fuse Iron. Therefore, we do not have the ability to study, in a lab if you like, such events.

Yes, you are right. There is so much we do not know about the processes that brought everything into existence. So many questions still unanswered. So many theories hypothesised, refined, refuted, revisited.

Philosophy and science are intertwined and contentious, but so what?

There is nothing wrong with thinking and questioning...

...and thinking and questioning outside the box. 

Newbie

Edited October 13, 2021 by Newbie