Can a powerful CME cause a comet to fragment?

[gdaniels99]

Is it possible for a coronal mass ejection from the sun to cause a comet to fragment?

For instance, I know CME's can cause extreme outgassing of a comet like Comet Holmes in 2007. And I've also seen NASA footage of a CME ripping off the plasma tail of Comet Encke:

http://www.nasa.gov/mission_pages/st...ews/encke.html

But could it actually cause a comet to break apart or at least break a large fragment off? If so, how large of a CME would be required to break a fragment off of a comet like Encke?

Or is this out of the realm of possibility?

[antoniseb]

... If so, how large of a CME would be required to break a fragment off of a comet like Encke?

Or is this out of the realm of possibility?

Encke's comet is pretty old and worn out. I doubt that any CMEs that've happened in recorded history would have been even a thousandth the energy required to cause enough outgassing to overcome self gravity. ... Now bear in mind that I haven't done the least bit of calculating here, but the energy conveyed per square meter by a CME, once you get out to Encke's orbit is very tiny, and even if you assume all of that energy gets converted to thermal energy, it won't get very far beyond the surface.

[gdaniels99]

I doubt that any CMEs that've happened in recorded history would have been even a thousandth the energy required to cause enough outgassing to overcome self gravity.

What about a CME that was able to cause z pinch auroras on earth? Would this be of significant magnitude to cause a breakup?

[tusenfem]

What about a CME that was able to cause z pinch auroras on earth? Would this be of significant magnitude to cause a breakup?

z-pinch aurorae? sounds like EU (Electric Universe) jargon.

Aurorae are caused by Earthward accelerated electrons (sometimes ions) that interact with the atmosphere.
For a CME to fragment a comet, it would have to have something to hit the cometary nucleus. Although there are tonnes of plasma in a CME the force it will exert on the nucleus is rather small based on the so-called ram pressure, which is in the area of nanoPascal.
The breaking off of the tail of the comet is a beautiful example of magnetic reconnection happening in the ion tail, however, has nothing to do with fragmeting the comet, as there is almost no mass in the tail, and the tail is no solid object.
I have no idea about the relation between CMEs and outgassing (maybe I will find it out when I start working on the Rosetta data, when it arrives at Churyomov-Gerasimenko in 2013). Googling on it, the only thing I find is this thread.

[gdaniels99]

Sorry, let me backtrack a minute and better explain where I'm coming from so you understand this isn't electric universe stuff.

OK, I read some research by Anthony Peratt where he showed (pretty convincingly, imho) that petroglyphs around the world which were all carved between 3000 BC- 2400BC showed accurate depictions of high energy plasma phenomena. He theorized that the only way primitive peoples all over the world could carve such accurate representations of plasma phenomena is if there had been a very high energy outburst from the sun (orders of magnitude larger than normal CMEs) which caused these designs to appear in the atmosphere as high energy aurora (which he calls z pinch aurora).

http://www.scribd.com/doc/14145750/A...d-in-Antiquity

In this research I also read that in 1969 astronauts discovered that a few recovered surface rocks on the moon showed signs of glazing and the only thing that could do this is if sometime in the past a very very large amount of energy zapped them. Peratt theorized that this was evidence that such a high energy event did happen in the past.

I also read research by astronomer Fred Whipple where he theorized that comet Encke has undergone at least two fragmentations in the past 5,000 years. One around 500 AD and one around 2400 BC. Napier & Clube have theorized fragments of Comet Encke hit the earth between 3000 BC- 2400 BC as well.

And researcher Dallas Abbott has theorized that the severe weather events of 536 AD were caused by an impact by a comet. This seems to coincide neatly with Whipple's Encke breakup of ~500 AD. I've read written accounts from this time period and one mentions a comet. Another mentions that the "sky seemed to be on fire." I take this latter comment as possibly meaning the earth was experiencing these z-pinch aurorae theorized by Perratt. I've also seen a Chinese Jade Ox from this time period which has a star symbol on its shoulder. Near this symbol are three fireballs. If the Ox represents the constellation Taurus and the star represents the Pleiades then these fireballs would seem to suggest they were part of the Taurids from comet Encke. You can see the jade ox at my website:

http://www.lostworlds.org/kolomoki_mounds.html

In other words, it seems these comet breakups and high energy outbursts from the sun are happening during the same time periods.

So here's where my question comes in: if an outburst from the sun could cause rocks on the moon to melt would that also be enough energy to possibly melt some of the ice in a comet, allowing some of the rocky particles to dislodge and become separated from the parent comet? Or is this still not enough energy to cause this type of fragmentation? Is the comet simply still too far away to be impacted by this event. Is it just coincidence that these two events seem to be happening simultaneously (z pinch aurora & comet fragmentation/impacts) or is there a real cause-effect connection?

Sorry, I don't mean to belabor the point. I just want to make sure we're operating from the same data. It seems logical that a CME strong enough to melt moon rocks could melt ice in a comet but then again, I don't know enough about how comets work to know what level of energy would be required to fragment one. So that's why I've asked you guys, the experts.

[jlhredshift]

There has been enough work done to determine how much energy is necessary to deflect comets/asteroids that I think that it is unlikely that a CME could have much of an effect.

[tusenfem]

OK, I read some research by Anthony Peratt where he showed (pretty convincingly, imho) that petroglyphs around the world which were all carved between 3000 BC- 2400BC showed accurate depictions of high energy plasma phenomena. He theorized that the only way primitive peoples all over the world could carve such accurate representations of plasma phenomena is if there had been a very high energy outburst from the sun (orders of magnitude larger than normal CMEs) which caused these designs to appear in the atmosphere as high energy aurora (which he calls z pinch aurora).

Although Peratt knows his way around plasma physics, this "research" is about as valid as the work from Erich von Däniken. I have seen the paper before, and I thought is was more "well this kind of looks the same, so it must be the same" reasoning.

In this research I also read that in 1969 astronauts discovered that a few recovered surface rocks on the moon showed signs of glazing and the only thing that could do this is if sometime in the past a very very large amount of energy zapped them. Peratt theorized that this was evidence that such a high energy event did happen in the past.

Well, the moon is old. Things have happened. It could have been deposits from space that have fallen too the moon, etc. etc. There is a lot of new info since Peratt's paper about materials generated at hot places in the solar system.

I also read research by astronomer Fred Whipple where he theorized that comet Encke has undergone at least two fragmentations in the past 5,000 years. One around 500 AD and one around 2400 BC. Napier & Clube have theorized fragments of Comet Encke hit the earth between 3000 BC- 2400 BC as well.

Cometary fragmentations are nothing unusual for old comets, various processes can fragment a nucleus, however, I am pretty sure a CME does not have the oomph for that.

And researcher Dallas Abbott has theorized that the severe weather events of 536 AD were caused by an impact by a comet. This seems to coincide neatly with Whipple's Encke breakup of ~500 AD. I've read written accounts from this time period and one mentions a comet. Another mentions that the "sky seemed to be on fire." I take this latter comment as possibly meaning the earth was experiencing these z-pinch aurorae theorized by Perratt.

Or, if a fragmented comet falls into the atmosphere and it burns up there, one would say that "the sky is on fire."

In other words, it seems these comet breakups and high energy outbursts from the sun are happening during the same time periods.

Well, no, you have not shown any evidence of that.

So here's where my question comes in: if an outburst from the sun could cause rocks on the moon to melt would that also be enough energy to possibly melt some of the ice in a comet, allowing some of the rocky particles to dislodge and become separated from the parent comet?

There is no evidence at all that the moon rock was melted by an outburst of the Sun.
The sunlight is constantly melting the ice of comets as they approach perihelion. This will possibly loosen parts of the surface of the nucleus.

Or is this still not enough energy to cause this type of fragmentation? Is the comet simply still too far away to be impacted by this event. Is it just coincidence that these two events seem to be happening simultaneously (z pinch aurora & comet fragmentation/impacts) or is there a real cause-effect connection?

There is little power in a CME (with respect to that needed for cometary fragmentation), like I said, the ram pressure is up to tens of nanoPascal.
There is always aurora, and z-pinch you can forget about, that is always there and is nothing special, because the main part of the aurora is caused by electrical currents flowing from the Earht's magnetotail, and these currents automatically are z-pinched because that is what currents in plasmas do.
Then again, the sources you give here are so vague that you can't do anything with them. Fragmentation ~500 AD, severe weather in 536, "the sky on fire" etc. It sounds nice if you put it together, but there it ends. You say: "Is it just coincidence that these two events seem to be happening simultaneously" but there has not even been shown that any of this stuff was simultaneously.

Is it just coincidence that these two events seem to be happening simultaneously
Sorry, I don't mean to belabor the point. I just want to make sure we're operating from the same data. It seems logical that a CME strong enough to melt moon rocks could melt ice in a comet but then again, I don't know enough about how comets work to know what level of energy would be required to fragment one. [/QUOTE]

But there is no evidence that a CME melted the rock on the Moon. Where would that energy come from?
The nucleus of a comet is made of a mixture of rock and ice. They were thought to be dirty snowballs, but have been found to be more like snowy dirtballs. The cohesion of the nucleus is pretty good, that is why we are landing "Philea" on Comet Churyamov-Gerasimenko, while Rosetta will go into orbit around it. It takes the strong gravitational pull of e.g. Jupiter to break up a comet, like what happened Shoemaker-Levy.

[Van Rijn]

For instance, I know CME's can cause extreme outgassing of a comet like Comet Holmes in 2007.

Do you have a reference on that? I don't recall a CME being implicated in the 2007 Comet Holmes event.

[tusenfem]

Comet Holmes lost its tail, interacting with a CME, if I am not mistaken. [ETA no I think I am mistaken here, Comet Holmes had a "flare up" whilst moving away from the Sun, and here is a list of peer reviewed papers on this comet]

Googling on "Comet Holmes CME" one gets this thread and threads in such trustworthy sites as "goldlikeproductions" "above top secret" and "thunderbolts" need I say more?

[gdaniels99]

Would the CME have enough energy to rip off the dust tail or only the ion tail?

Van Rijm: I'm thinking I must've dreamed it! I could've sworn I read a journal article where a solar flare could cause outgassing. Now no combination of search terms turns up said journal article. :/

[tusenfem]

Would the CME have enough energy to rip off the dust tail or only the ion tail?

The impact of the plasma in a CME can mess up the dust tail, I think, like blowing against cigarette smoke mixes things up, but not "rip it off" because the dust is neutral and not connected to anything, it is just trailing the comet in its orbit.

The ion tail, however, has the ions connected to the solar wind magnetic field, when the CME passes by the magnetic field can reconnect and with that part of the tail gets disconnected. That happened to Comet Encke, and a movie of it can be seen here on wikipedia.

[gdaniels99]

Apparently Comet Elenin broke apart right after being hit by a CME which suggests comets CAN break apart due to such an event despite all the arguments to the contrary in this thread. Here's the quote from UniverseToday:

"On August 19, a massive solar flare and coronal mass ejection hit the comet, which may have been the beginning of the end for the much ballyhooed lump of ice and dirt. 'We’ve been following it in the STEREO spacecraft images and a number of amateurs have been following it in their telescopes,' said Australian amateur astronomer Ian Musgrave, author of the Astroblog website. 'Shortly after the coronal mass ejection the comet flared up and you could see some beautiful details in the tail, with the tail was twisting about in the solar wind. But shortly after that Earth- bound amateurs reported a huge decrease in the intensity of the comet. We think it may presage a falling apart of the comet.'"

http://www.universetoday.com/88494/c...isintigrating/

It appears my original idea of a CME causing a violent outgassing could, in fact, be a plausible way for a comet to break apart due to such an event. So I'd love to hear what the "experts" who denied such a thing was possible have to say now.

[kheider]

We know that Comet Elenin dimmed after being hit by a CME. We do not known exactly when the comet started fragmenting. The comet could have fragmented before the CME hit. Thermal stress from the Sun had been working on the nucleus as the comet approached perihelion.

-- Kevin Heider

[tusenfem]

The interaction of the CME with comet Elinin is understandable. There has been a lot of outgassing of the comet as it nears the Sun. There will also be a lot of debris gas/dust around the comet in the coma. The highly energetic and denser plasma of the CME will interact strongly with the come, making it "flare up" because there is a shock at the front of the CME. This effect peters down again after the CME has passed, and a dimming was observed of the comet.

As to the fragmentation, I am still dubious that the strength of a CME would be enough to break it up. I cannot find any reference of comets being disintegrated by a CME impact, here is a paper about Comet Enke but basically all that happens with a CME is an electrodynamic interaction.

(although we do have the running gag here that, when Philae will land on Comet CG and will deploy its harpoon, the comet will shatter in billions and billions of pieces)

And also not that the article says "We think it may presage a falling apart of the comet." The dimming of the comet would be the presage.
From the Universe Today article: "Some astronomers predict the comet will disintegrate and not survive perihelion, its closest approach to the Sun."
And there is as yet no image as e.g. for Comet S4 Linear (also in the UT article) of it breaking up.
Perihelion is on September 23, and after that SOHO should be able to observe it.

[iantresman]

Is it possible for a coronal mass ejection from the sun to cause a comet to fragment?

I would argue that comets may fragment due to internal changes of force, and this change of force may be due to changes in the amount of energy it receives. There is no doubt that a comet changes when they receive extra energy from the Sun (ie. generate a tail). A coronal mass ejection (CME) produces extra energy, that may also be received by the comet. We know that CMEs may cause cities on Earth to blackout, so it seems reasonable to me, that a CME may contribute significant energy that triggers the break of the camel's back (to mix a few metaphors).

The poster asked whether it was possible. I think the argument is in the affirmative, but that it would be difficult to prove that it was solely responsible.

[Shaula]

OK so where in your average comet are long thin conductors? The electricity grid failures have nothing to do with any forces and everything to do with induction. It is rather like saying "I know this computer virus can render my computer useless, therefore it must be able to damage this shovel".

[iantresman]

Although Peratt knows his way around plasma physics, this "research" is about as valid as the work from Erich von Däniken. I have seen the paper before, and I thought is was more "well this kind of looks the same, so it must be the same" reasoning.

• As far as I know, von Däniken had no peer-reviewed paper. Peratt's has many peer-reviewed papers (including conference records) His main papers appear to be here and here (full text versions can be found via Google)
  
• I believe that von Däniken provides very few examples to support his work. Peratt's abstract in his second paper mentions contributions "from 139 countries, from sites and fields containing several millions of these objects."
  
• Peratt's papers indicate that he considers more than just a trivial "kind of looks the same".

I am not providing an assessment, nor condoning Peratt's work, only that his comparison to von Däniken appears to be unfair.

[iantresman]

OK so where in your average comet are long thin conductors? The electricity grid failures have nothing to do with any forces and everything to do with induction. It is rather like saying "I know this computer virus can render my computer useless, therefore it must be able to damage this shovel".

Yes, different mechanisms, but both are due to an increase in energy. If you add energy to any system, stuff may happen!

[Strange]

[list][*]As far as I know, von Däniken had no peer-reviewed paper. Peratt's has many peer-reviewed papers

And yet, none of these are published in journals related to, say, architecture. So all the reviewers can do is say that none of his statements regarding plasma are wrong. Not exactly a ringing endorsement.

I believe that von Däniken provides very few examples to support his work. Peratt's abstract in his second paper mentions contributions "from 139 countries, from sites and fields containing several millions of these objects."

Quantity != quality.

I am not providing an assessment, nor condoning Peratt's work, only that his comparison to von Däniken appears to be unfair.

On the face of it, it seems an entirely reasonable comparison. Unless there are some acknowledged experts in the relevant fields (i.e. not plasma physics) who endorse his ideas.

[tusenfem]

We know that CMEs may cause cities on Earth to blackout, so it seems reasonable to me, that a CME may contribute significant energy that triggers the break of the camel's back (to mix a few metaphors).

No, we know that a CME can interact with the magnetic field of the Earth, causing a very strong interaction (e.g. a substorm), which might induce strong currents in the electricity net and through the Earth proper at high latitudes.
The induced magnetosphere of a comet (basically solar wind magnetic field line draping) is not capable of storing that much energy, and as there is most likely no electricity net on the comet, it would be difficult to create a black out there.
Nor do I see how the electrodynamics of this interaction will tear the cometary nucleus apart. If you have any peer reviewed evidence for such a suggestiong I would be very interested.

As far as I can see, no it is not possible.

[tusenfem]

[list][*]As far as I know, von Däniken had no peer-reviewed paper. Peratt's has many peer-reviewed papers (including conference records) His main papers appear to be here and here (full text versions can be found via Google)

Sure, but even someone with peer reviewed papers can write bunk papers, like this petroglyph paper.
And the paper is still as bunk as Von Däniken's work.

[iantresman]

And yet, none of these are published in journals related to, say, architecture. So all the reviewers can do is say that none of his statements regarding plasma are wrong. Not exactly a ringing endorsement.

Yes, that's the problem with interdisciplinary papers, do you publish in plasma journals, astronomy, archaeology, archaeoastronomy, magnetospherics, etc. Either way, Peratt's peer-reviewed papers can be obtained and read by anyone.

Quantity != quality.

I think you mean that one does not imply the other, but large data sets are a good thing, as any statistician will attest.

On the face of it, it seems an entirely reasonable comparison. Unless there are some acknowledged experts in the relevant fields (i.e. not plasma physics) who endorse his ideas.

Sorry, but I think that is a non sequitur. The same sort of thing happened to Alfvén when he published his papers on MHD, which was ignored until Enrico Fermi gave it the metaphorical thumbs up (ref). But I'm not aware of anyone having compared Alfvén's work to, for example, Charles Fort, just because it hadn't been "approved".

Again, I'm not assessing Peratt's work in any way, only criticising the comparisons.

[iantresman]

The induced magnetosphere of a comet (basically solar wind magnetic field line draping) is not capable of storing that much energy, and as there is most likely no electricity net on the comet, it would be difficult to create a black out there.
Nor do I see how the electrodynamics of this interaction will tear the cometary nucleus apart. If you have any peer reviewed evidence for such a suggestion I would be very interested.

I wasn't trying to imply that any transfer of energy from a CME to a comet was due to electrodynamics. I just said that a CMI includes extra energy. Comets get energy from the Sun's electromagnetic radiation. A proportion of a CME's energy is also electromagnetic radiation. A comet encountering a CME would receive more electromagnetic radiation energy than that derived from the Sun alone.

I have no idea how much extra energy a comet may (or may not) receive in this way, but IF it is measurable, then it may be significant.

I also don't see how the electrodynamics of a comet's tenuous magnetosphere could affect its nucleus, unless there was a mechanism to convert the electromagnetic energy into heat.

[iantresman]

Sure, but even someone with peer reviewed papers can write bunk papers, like this petroglyph paper.
And the paper is still as bunk as Von Däniken's work.

I would like to think that you would have taken a more investigative approach., but you're entitled to your opinion, even though I believe I have shown that there is no comparison due to significant differences in their work.

[Strange]

Sorry, but I think that is a non sequitur. The same sort of thing happened to Alfvén when he published his papers on MHD, which was ignored until Enrico Fermi gave it the metaphorical thumbs up (ref). But I'm not aware of anyone having compared Alfvén's work to, for example, Charles Fort, just because it hadn't been "approved".

I'll see your non sequitur and raise you: Alfven's work was in his own area of expertise. That it took time for a new idea to be accepted (and, as is often the case, one person to "break the ice") is not the same as if he had come up with a theory that the pyramids had been built using plasma technology. I'm not sure that Fermi, or anyone else, would have given that the thumbs up.

[iantresman]

I'll see your non sequitur and raise you: Alfven's work was in his own area of expertise. That it took time for a new idea to be accepted (and, as is often the case, one person to "break the ice") is not the same as if he had come up with a theory that the pyramids had been built using plasma technology. I'm not sure that Fermi, or anyone else, would have given that the thumbs up.

OK, call.

My point is that the quality of a person's work does not become more or less scientific, depending on who reads it. However, the outcome may do so. For example, if I ask you to do some scientific research on ghosts (for want of a better example), and no scientists read it (of course they know better), that doesn't mean that your science is necessarily bad. The science is bad when someone finds something scientific improper with it, eg. bad experimentation, bad statistics, bad assumptions, etc.

Science requires work to be peer reviewed. A peer-reviewed paper is a step in the right direction. There are indeed other hurdles to cross.

[Strange]

The science is bad when someone finds something scientific improper with it, eg. bad experimentation, bad statistics, bad assumptions, etc.

Agreed. It makes me wonder why none of his work has been published in journals more relevant to the other aspects of his theory. Has he tried and it was rejected out of hand for being too "out there"; has he tried and it was rejected after peer reviewers pointed out all the flaws in their fields of expertise; has he not even tried because he knows the only places that will accept it are those who cannot fault his work wrt plasma; or other reasons I can't think of right now... (the Illuminati don't want the Truth to come out or something )

[iantresman]

Agreed. It makes me wonder why none of his work has been published in journals more relevant to the other aspects of his theory. Has he tried and it was rejected out of hand for being too "out there"; has he tried and it was rejected after peer reviewers pointed out all the flaws in their fields of expertise; has he not even tried because he knows the only places that will accept it are those who cannot fault his work wrt plasma; or other reasons I can't think of right now... (the Illuminati don't want the Truth to come out or something )

I don't know whether he has tried other journals. Certainly he has had papers published in other astronomy/physics journals (see my previous link). I can speculate that perhaps he felt that as a plasmas physicist, he would write plasma physics papers that would be better assessed by other plasma physicists. If I was writing a paper on petroglyphs, and it was based on plasma physics, I wouldn't know what to include to make it acceptable to the petroglyph community; you couldn't remove the plasma science, because then you could be accused of having insufficient science!

The other point you mention concerning fields of expertise, begs the question. How do you assess expertise in a potentially new field? But that's probably for another thread.

Another thought occurs to me. Alfvén said that he had a hard time getting his papers published in the relevant journals because editors and referees did not understand his papers (how could they, it was new physics!).

[antoniseb]

... It appears my original idea of a CME causing a violent outgassing could, in fact, be a plausible way for a comet to break apart due to such an event. So I'd love to hear what the "experts" who denied such a thing was possible have to say now.

What I denied was that Encke's Comet would be likely to break up this way. Elenin is a much newer comet, and also a much smaller nucleus. The gravitational forces are much lower, and the gas forces are much stronger. It is very common for small new comets to break up. The CME may or may not have been "the straw that broke the camel's back", to use a rough analogy.

[Strange]

If I was writing a paper on petroglyphs, and it was based on plasma physics, I wouldn't know what to include to make it acceptable to the petroglyph community

Hmmm... and that is kinda my problem: if he doesn't know what to include to make it acceptable to the petroglyph community, then that casts some doubt on his expertise. (I'm not saying that is the case, necessarily, but if...)

The other point you mention concerning fields of expertise, begs the question. How do you assess expertise in a potentially new field? But that's probably for another thread.

Well, new fields sometimes come about through interdisciplinary work, so have a mixture of expertise from the start. Which raises another question: is this his own "personal" theory of has he collaborated with archaeologists, petroglyphists, etc.

Another thought occurs to me. Alfvén said that he had a hard time getting his papers published in the relevant journals because editors and referees did not understand his papers (how could they, it was new physics!).

Someone raised a similar point about Bose-Einstein statistics in another thread.