67P, why erosion from the neck?

[viscount aero]

In my opinion, a key to understanding the comet is the chemistry in relation to the Solar plasma. This relationship is that of an acid (solar wind) (H+) and a base (the comet) (OH-). This interaction and presence of ions is evidence for an electrolytic environment.

from:
https://chemistry.osu.edu/~woodward/ch121/ch4_acids.htm

Acids and Bases

Acid: A substance which ionizes to form H+ (H+ is a product).

Examples

HNO3(aq): H+(aq) + NO3-(aq)

HCl(aq): H+(aq) + Cl-(aq)

Base: A substance that accepts (reacts with) H+.

Examples

OH-(aq) + H+(aq) = H2O(l)

NH3(aq) + H+(aq)= NH4+(aq)

Note that to obtain hydroxide ions (OH-) we start with an ionic compound that dissolves in water to form hydroxide ions, such as the alkali metal hydroxides, LiOH, NaOH, KOH, RbOH, etc.

Since both acids and bases dissolve in water to form ions, they are both electrolytes.

[willendure]

Back to your hypothesis, if the rotation of the comet is generating a magnetic field (i.e., a dynamo effect)

Hi,

On this point, could the magnetic field have come into being something like this:

Rock tumbling through space, solar wind strips of some of its material as OH-. The rock is now charged and rotating, hence it has a magnetic field, always with the pole perpendicular to the rotation.

As more OH- is stripped off, it get more charged, increasing the magnetic field, and consequently concentrating the solar wind onto its poles. A positive feedback.

It doesn't matter too much if the comet rotates a bit (very graudually) around an axis along the neck, as the magnetic field is always perpendicular to the principal axis of rotation. This would simply lead to a "shifting" pole, and more even erosion all around the neck, instead of just on two fixed sides of the neck.

[CharlesChandler]

In short, corrosion is defined as the deterioration of a metal by a chemical or electrochemical reaction with its environment. If 67P is typical, then Wild 2/Stardust return samples shed clues on cometary composition: What was found was an abundance of olivine (a mineral group)--a magnesium-iron-silicate, and and pyroxene, a high-heat originating silicate. To wit, a comet is a metallic silicate. And it happens that Mg and Fe are highly vulnerable to corrosion.

In my opinion, a key to understanding the comet is the chemistry in relation to the Solar plasma. This relationship is that of an acid (solar wind) (H+) and a base (the comet) (OH-). This interaction and presence of ions is evidence for an electrolytic environment.

Dude, that makes a LOT of sense. I agree that the comet is negatively charged, and that the interplanetary medium is positively charged. So something is going to happen. And yes, it would be more like corrosion, since it is chemical, as opposed to erosion, which is physical. It looks like you're well on your way to nailing it down. Follow through on it, and post your conclusions to vixra.org.

Be sure to review the facts that Wal collected (see below) concerning the chemistry of comets and comas (even if you don't necessarily come to the same conclusion). I think that it's corrosion and photo-ionization that is doing the work. FWIW, I don't think that all of the material in the coma actually came from the comet -- I think that a lot of it is just the IPM that got stirred up as the comet passed through. With a supersonic shock from the combined velocities of the comet and the solar wind, the comet will have a charged sheath around it, and as the IPM impinges on this sheath, the ions get embedded deeper than the electrons, due to their greater mass. This creates a positively charged sheath of plasma surrounding the comet, which could easily have a much greater charge than the IPM. Once the comet has passed, the electrons and +ions will eventually recombine, while the chemical composition might have changed a bit from the IPM, with the ionization and recombination possibly forming new compounds. But at least some of what glows in the coma didn't come from the comet -- it was just matter that got ionized by friction when the IPM slammed into the detached bow shock in front of the comet, and the subsequent charge recombination causes it to glow.

http://www.thunderbolts.info/thunderblo ... e_teu2.htm

Deep Impact saw absolutely no evidence for any ice on the surface of comet Tempel 1. At 56 °C (133 °F) on the sunlit side it was too hot for ices. However, it was reported that there's plenty of ice visible in Tempel 1's coma.

On viewing comet comas spectroscopically and observing the hydroxyl radical (OH), astronomers simply assume it to be a residue of water ice (H2O) broken down by the ultraviolet light of the Sun (photolysis). This assumption requires a reaction rate due to solar UV radiation beyond anything that can be demonstrated experimentally.

A report in Nature more than 25 years ago cast doubt on this mechanism. As Comet Tago-Sato-Kosaka moved away from the Sun, OH production fell twice as fast as that of H, and the ratio of OH:H production was lower than expected if H2O was dominant. The report concludes, “cometary scientists need to consider more carefully whether H2O-ice really does constitute a major fraction of comet nuclei.”

The mystery of ‘missing water’ is resolved electrically in the transaction between a negatively charged comet and the Sun. In this model, electrical discharges strip negative oxygen ions from rocky minerals on the nucleus and accelerate the particles away from the comet in energetic jets. The negative ions then combine with protons from the solar wind to form the observed OH radical, neutral H2O and H2O+.

Alfvén and Gustav Arrhenius note, “The assumption of ices as important bonding materials in cometary nuclei rests in almost all cases on indirect evidence, specifically the observation of atomic hydrogen and hydroxyl radical in a vast cloud surrounding the comet, in some cases accompanied by observation of H20+ or neutral water molecules.” *

The abundance of silicates on comet nuclei, confirmed by infrared spectrometry, led the authors to cite experiments by Arrhenius and Andersen. By irradiating the common mineral, calcium aluminosilicate (anorthite), with protons in the 10 kilovolt range, the experiments “resulted in a substantial (~10 percent) yield of hydroxyl ion and also hydroxyl ion complexes [such as CaOH.]”

A good reason for the experiments was already in hand. Observations on the lunar surface reported by Hapke et al., and independently by Epstein and Taylor had “already demonstrated that such proton-assisted abstraction of oxygen (preferentially 016) from silicates is an active process in space, resulting in a flux of OH and related species.”

The authors note in addition that this removal of oxygen from particles of dust in the cometary coma could be much more efficient than on a solid surface with limited exposure to available protons: “The production of hydroxyl radicals and ions would in this case not be rate-limited by surface saturation to the same extent as on the Moon.”

The authors conclude: “These observations, although not negating the possible occurrence of water ice in cometary nuclei, point also to refractory sources of the actually observed hydrogen and hydroxyl.” Additionally, they note, solar protons as well as the products of their reaction with silicate oxygen would interact with any solid carbon and nitrogen compounds characteristic of carbonaceous chondrites to yield the volatile carbon and nitrogen radicals observed in comet comas.

*H Alfvén and Gustav Arrhenius, Evolution of the Solar System, NASA SP-345, 1976, p. 235.

[CharlesChandler]

Rock tumbling through space, solar wind strips of some of its material as OH-. The rock is now charged and rotating, hence it has a magnetic field, always with the pole perpendicular to the rotation.

Yes! Also, as the positive sheath builds up around the outside of the comet, it will induce a negative charge on the surface. If that's all there was to it, the comet would be net neutral. But still it's rotation would create a dynamo. The reason is that the outer layer, which is negative, has a greater angular velocity than the inside of the comet, which is positively charged (if the whole thing is net neutral). So the greater angular velocity generates the dominant magnetic field. And of course if you have a net charge, you get an even stronger field.

[Solar]

“We will be able tell what is happening on the lander by the changes in its magnetic field,” says ROMAP co-principal investigator Hans-Ulrich Auster.

These measurements will add to the overall picture of Philae’s progress to the surface of the comet.
Of course, the main focus of these instruments is on science. The comet should retain a memory of any magnetic field that was present in its environs 4.6 billion years ago when the Earth and the other planets were forming. For example, some theories of star and planet formation require a magnetic field to accelerate the growth of our Solar System, while others do not, and thus by measuring the ‘fossil’ field, Rosetta can hope to shed light on this epoch.
In the final few hundred metres of Philae’s descent, ROMAP will detect this magnetic fossil if it exists.

“It’s a simple question, is it there: yes or no. We are just a few days away from knowing the answer to this,” says Auster. – Tracking Philae’s descent with magnetic data

Nice 'electrochemical corrosion' hypothesis Vis.

Linked to the ROMAP magnetometer data that informed ESA of what was occurring with lander deployment including separation of Philae, boom deployment and, bouncing/landing on the surface of the comet.

I don't understand their analysis in the quoted section above. Sure, a comet can have a magnetic field. However, should not this magnetic field change owing to a charged body in motion having a magnetic field induced about it in order to repel an applied mag field?? They are assuming that the mag field of the comet is of the same intensity as the one it supposedly had billions of years ago ("fossil field")?? The comet is in the different environment of the interplanetary magnetic field of this solar system now. Where is that relationship in their analysis, or am I missing something?

[viscount aero]

In short, corrosion is defined as the deterioration of a metal by a chemical or electrochemical reaction with its environment. If 67P is typical, then Wild 2/Stardust return samples shed clues on cometary composition: What was found was an abundance of olivine (a mineral group)--a magnesium-iron-silicate, and and pyroxene, a high-heat originating silicate. To wit, a comet is a metallic silicate. And it happens that Mg and Fe are highly vulnerable to corrosion.

In my opinion, a key to understanding the comet is the chemistry in relation to the Solar plasma. This relationship is that of an acid (solar wind) (H+) and a base (the comet) (OH-). This interaction and presence of ions is evidence for an electrolytic environment.

Dude, that makes a LOT of sense. I agree that the comet is negatively charged, and that the interplanetary medium is positively charged. So something is going to happen. And yes, it would be more like corrosion, since it is chemical, as opposed to erosion, which is physical. It looks like you're well on your way to nailing it down. Follow through on it, and post your conclusions to vixra.org.

Be sure to review the facts that Wal collected (see below) concerning the chemistry of comets and comas (even if you don't necessarily come to the same conclusion)...

Many thanks, Charles. That means a lot coming from you. I am going to write this one up

I'd like you (and the whomever wishes to read it) to critique it once I have a readable working draft.

[CharlesChandler]

I'd like you (and the whomever wishes to read it) to critique it once I have a readable working draft.

Cool -- just let us know when you have something. Cheers!

[viscount aero]

Back to your hypothesis, if the rotation of the comet is generating a magnetic field (i.e., a dynamo effect)

Hi,

On this point, could the magnetic field have come into being something like this:

Rock tumbling through space, solar wind strips of some of its material as OH-. The rock is now charged and rotating, hence it has a magnetic field, always with the pole perpendicular to the rotation.

Yes as long as there is an ionization, OH-, then the surface is charged. This is why Cassini was hit by a discharge from Hyperion. A charge sep occurred and a circuit was closed.

Although too brief, this PR confirms that mainstream science has taken at least a casual note of this but falls short of going deeper into the phenomenon:

excerpt:
http://www.space.com/27466-cassini-spac ... erion.html

"Researchers have long known that static electricity is an important phenomenon on Earth's moon. However, this is the first time they have confirmation of static at play on another cosmic body. Luckily, the beam didn't seem to harm Cassini, but future robotic and crewed missions should be wary of possible electric shocks from bodies in the solar system, researchers said.

"Our observations show that this is also an important effect at outer planet moons, and that we need to take this into account when studying how these moons interact with their environment," Geraint Jones, a member of the Cassini Plasma Spectrometer instrument team who helped supervise the study, said in the same statement."

Of course they don't whatsoever make any connection of this physics to comets or asteroids because they are too preoccupied with looking for water ice, seeing comets only as the evolutionary "missing link" species as being "primordial planet-forming artifacts that created all oceans and brought biology of Earth."

Until they drop that entire mode of thinking then no wider consideration of the Cassini/Hyperion discharge event will take place despite the lip-service they pay to the subject. Water having been carried to Earth from comets to create the oceans is utterly ridiculous of an idea and never took place. But this is the core premise of their bias and science which all data is viewed through.

As more OH- is stripped off, it get more charged, increasing the magnetic field, and consequently concentrating the solar wind onto its poles. A positive feedback.

It doesn't matter too much if the comet rotates a bit (very graudually) around an axis along the neck, as the magnetic field is always perpendicular to the principal axis of rotation. This would simply lead to a "shifting" pole, and more even erosion all around the neck, instead of just on two fixed sides of the neck.

I haven't found a way to fully explain the selective or biased corrosion that appears to happen in a 360º radial, circumpolar, fashion on 67P (and others). I'm considering wild exceptions where there is an asymmetry, a seeming chaos, of a mag field's orientation relative to planetary rotation as is seen on Neptune. Neptune seems to bend all the rules. Therefore an "absolute state" of a magnetic field relative to a polar rotation cannot be considered.

My corrosion hypothesis entails many things not yet discussed such as specific types of corrosion. For example this:

"Crevice corrosion results from intense localized attack, usually associated with small volumes of stagnant solutions in shielded areas while the remaining surface experiences little or no damage. For example, contact between metal and nonmetallic surfaces can result in crevice corrosion. A sheet of 18% chromium and 8% nickel stainless steel can be cut by placing a stretched rubber band around it and then immersing it in seawater."

I'm looking for the celestial "rubber band" around 67P

[justcurious]

My own theory is that the interior is porous, so once one part of the comet starts getting eroded away by electrical discharging, jagged parts are exposed which are more prone to electrical discharge. Also, charge is concentrated where there is higher curvature, so the neck area would have a higher concentration of charges as seen from far. Or perhaps the interior of the comet has a different composition than the surface which makes it more prone to discharge, once the erosion starts in one area, it would ted to continue there. These are wild speculations, but I think they are better than any other explanations I have seen or heard so far.

[willendure]

I'd like you (and the whomever wishes to read it) to critique it once I have a readable working draft.

Cool -- just let us know when you have something. Cheers!

Would love to read it too.

I think there is a testable hypothesis, as I said earlier, if we look at the shape and axis of rotation of other comets, in relation to 67P.

[viscount aero]

I'd like you (and the whomever wishes to read it) to critique it once I have a readable working draft.

Cool -- just let us know when you have something. Cheers!

Would love to read it too.

I think there is a testable hypothesis, as I said earlier, if we look at the shape and axis of rotation of other comets, in relation to 67P.

Thanks, willendure. I will look up other comet's axes/rotations.

[CharlesChandler]

My own theory is that the interior is porous...

I agree with the porosity thing, but I don't think that it's just the interior. I'm starting to think of comets & asteroids as the fragments of a celestial collision (i.e., Theia versus Ceres). Some of the fragments fell into a regular orbit in the asteroid belt, while others fell into the Sun, or were responsible for the cratering during the Late Heavy Bombardment. Still others are in highly elliptical orbits, not having collided with anything (yet). The largest fragment collided with the Earth, and is still in orbit around it (i.e., the Moon). The rock-like appearances of asteroids & comets, and their low densities, would then make them like pumice, which was magma with dissolved gases that came out of solution as they cooled.

I do not think that they formed by accretion, making them like overgrown dust bunnies, but which would be much, much lower in density.

[viscount aero]

My own theory is that the interior is porous, so once one part of the comet starts getting eroded away by electrical discharging, jagged parts are exposed which are more prone to electrical discharge. Also, charge is concentrated where there is higher curvature, so the neck area would have a higher concentration of charges as seen from far. Or perhaps the interior of the comet has a different composition than the surface which makes it more prone to discharge, once the erosion starts in one area, it would ted to continue there. These are wild speculations, but I think they are better than any other explanations I have seen or heard so far.

The low density, high porosity, is typical of rapidly cooled blast furnance slag. Comets are more than likely dross or trash leftovers from a cataclysm, pieces of celestial waste slag flying off a destroyed planetary mantle.

Stardust/Wild 2 pyroxenes and olivines (metallic silicates) are indicative of hellish origins of comets that underwent rapid cooling in the possible presence of water vapor. Volcanism and tectonics, geology, tends to be infused with water, at least hydroxyls, as part of the rock's "dry" structure. This premise will appear in my writeup.

For example:
http://www.ncbi.nlm.nih.gov/pubmed/17066032

excerpt: "... Geophysical observations such as electrical conductivity are considered to be sensitive to water content, but there has been no experimental study to determine the effect of water on the electrical conductivity of olivine, the most abundant mineral in the Earth's mantle. Here we report a laboratory study of the dependence of the electrical conductivity of olivine aggregates on water content at high temperature and pressure. The electrical conductivity of synthetic polycrystalline olivine was determined from a.c. impedance measurements at a pressure of 4 GPa for a temperature range of 873-1,273 K for water contents of 0.01-0.08 wt%. The results show that the electrical conductivity is strongly dependent on water content but depends only modestly on temperature. The water content dependence of conductivity is best explained by a model in which electrical conduction is due to the motion of free protons."

And this about water-rich ringwoodite, excerpt from:
http://www.livescience.com/46292-hidden ... antle.html

"A water-rich mineral

Ringwoodite is a rare type of mineral that forms from olivine under very high pressures and temperatures, such as those present in the mantle's transition zone. Laboratory studies have shown that the mineral can contain water, which isn't present as liquid, ice or vapor; instead, it is trapped in the ringwoodite's molecular structure as hydroxide ions (bonded oxygen and hydrogen atoms)."

Outlined above may be the bare essence of a cometary body and its nature. Yet despite hard science and data as outlined above (which is only a fraction of science available), modern astronomers are thinking that the cometary "ringwoodite" is a literal fluffy porous snowcone covered in a little dirt that you can eat with flavored syrup. Boy are they wrong.

[Frantic]

Viscount I had speculated something similar to what you are thinking awhile back. I don't know if this would work, but what I was thinking is something like this :

Forsterite + water → serpentine + brucite

2Mg2SiO4 + 3H2O → Mg3Si2O5(OH)4 + Mg(OH)2 →

Mg3Si2O5(OH)4 + Mg(OH)2+ 6H (solar wind)→ 6H2O + Mg3Si2O5 + Mg

the 6H2O incorporates into the coma and eventually combines once again with fosterite, creating the "aquesous rock"

The water infusing into the rock creates the material to be eroded, the location of the aqueous rock may not be uniform do to the initial or continual depositing of water in a preferential location. Hence the subsequent erosion from that location. I think it is a balanced equation that is variable based on solar wind input.

I struggle a little bit with understanding the electrolytic environment you describe and even the process I am describing as I am no chemistry expert, but keep working on it.

additionally :

In the presence of carbon dioxide, however, serpentinitization may form either magnesite (MgCO3) or generate methane (CH4). It is thought that some hydrocarbon gases may be produced by serpentinite reactions within the oceanic crust.

my original post :

Why would they think it is shooting out neutral particles. Am I right in thinking that you would be seeing ionization of the comet materials, which than causes the ejection of ions or electrons allowing for all the different compounds so far detected. The water forming from the solar wind and hydroxyl is further evidence of this. Maybe just a miss-wording.

Question, could it make sense that if we have H+ from solar wind and OH- from the comet, that something like the following could be maintaining a balance with the erosion of the comet and input of the solar wind. Any H20 being produced is entering into these reactions.

Reaction 1a:
Fayalite + water → magnetite + aqueous silica + hydrogen

3Fe2SiO4 + 2H2O → 2Fe3O4 + 3SiO2 + 2H2

Reaction 1b:
Forsterite + aqueous silica → serpentine

3Mg2SiO4 + SiO2 + 4H2O → 2Mg3Si2O5(OH)4

Reaction 1c:
Forsterite + water → serpentine + brucite

2Mg2SiO4 + 3H2O → Mg3Si2O5(OH)4 + Mg(OH)2


I think when this has been looked at before all assumptions are based on water in the asteroid/comet being within the body, and consumed overtime, as opposed to a dynamic input, there conclusions therefore would be different than if they had considered water external to the body as a primary source. This takes away the assumption of a nice slow gradual consumption of a known quantity of water that works so well for math. It is a dynamic input difficult to quantify.

[viscount aero]

Viscount I had speculated something similar to what you are thinking awhile back. I don't know if this would work, but what I was thinking is something like this :

Forsterite + water → serpentine + brucite

2Mg2SiO4 + 3H2O → Mg3Si2O5(OH)4 + Mg(OH)2 →

Mg3Si2O5(OH)4 + Mg(OH)2+ 6H (solar wind)→ 6H2O + Mg3Si2O5 + Mg

the 6H2O incorporates into the coma and eventually combines once again with fosterite, creating the "aquesous rock"

The water infusing into the rock creates the material to be eroded, the location of the aqueous rock may not be uniform do to the initial or continual depositing of water in a preferential location. Hence the subsequent erosion from that location. I think it is a balanced equation that is variable based on solar wind input.

I struggle a little bit with understanding the electrolytic environment you describe and even the process I am describing as I am no chemistry expert, but keep working on it....

Frantic, good points.

If you can, work on chemical reactions that account for the existence of the following (which has thus far been detected). Some of these may be products of a chain reaction (which implies creation of the molecules above the surface of the comet), and some may be purely existing on the comet:

Water (H2O)

Carbon monoxide (CO)

Carbon dioxide (CO2)

Ammonia (NH3)

Methane (CH4)

Methanol (CH3OH)
Formaldehyde (CH2O)

Hydrogen sulphide (H2S)

Hydrogen cyanide (HCN)

Sulphur dioxide (SO2)

Carbon disulphide (CS2)

Keep in mind the known elements in the solar wind. The cited article below is quite honest in its assessment of what the 'wind" really is:

excerpt from:
http://solar-center.stanford.edu/FAQ/Qsolwindcomp.html

"The composition of the solar wind is a mixture of materials found in the solar plasma, composed of ionized hydrogen (electrons and protons) with an 8% component of helium (alpha particles) and trace amounts of heavy ions and atomic nuclei: C, N, O, Ne, Mg, Si, S, and Fe ripped apart by heating of the Sun's outer atmosphere, that is, the corona (Feldman et al., 1998).

SOHO also identified traces of some elements for the first time such as P, Ti, Cr and Ni and an assortment of solar wind isotopes identified for the first time: Fe 54 and 56; Ni 58,60,62 (Galvin, 1996).

Note that although the solar wind is electrically balanced, the solar wind consists almost exclusively of charged particles (stripped away nuclei from atoms) and is an excellent electrical conductor. These electrically conducting particles is technically known as a plasma, so it may be misleading to think of the solar wind as like Earth "winds"."