I've been thinking about the CME event that contacted comet Elenin on the 19th of August and have wondered if the CME somehow caused the decrease in observable activity as well as the elongation of the inner coma seen for a few days after the event. Had there been no CME event I would, like everyone else, assume that what we were seeing was the result of an ordinary breakup and disintegration. However, with the CME in play something completely different could be happening. This started me thinking about what would happen if a polarized CME contacted a comet in such a way that the nucleus became either negatively or positively charged. Would the charge prevent the normal formation and visual activity of the coma and or tails? Is this what has happened with comet Elenin? Could this also be an explanation for the two known spectacular outbursts of comet Holmes?
Let's say that because a CME originates at an area of intense magnetic fields, that those magnetic fields at the moment of ejection sometimes cause a separation of charge on rare occasions, such that, a cloud of charge, both negative and positive flows out with the normal plasma ejecta. And then, this charge cloud contacts the nucleus of a comet in such a way that only the positively or negatively charged part of the ejecta cloud makes contact. How would this contact occur dynamically and what would be the effects of this charge residing on the surface of the nucleus?
There are numerous dynamic electric field and magnetic field interactions that can be envisioned, but I want to propose an interaction that covers the elongation of the inner coma of comet Elenin as a start. A negative charging event would have less inertia and would be very different from a positive charging event having more inertia and to get a good visualization of the dynamics a numerical simulation would be needed, however, one effect that might occur is the slowing down of the alpha or beta charges as a result of colliding with the coma, thus forming a magnetic field. This magnetic field would either have a focusing of charge on the nucleus or a deflection of charge, depending on whether the charge cloud was negative or positive. Once the nucleus was charged the resulting electric field would then begin to effect the normal flow of the solar wind in various ways depending on whether the nucleus ended up being negatively or positively charged. This solar wind flow interaction with the electric field would need to be such that the nucleus could not be readily neutralized either by means of the effects of a electric field and inertia or the effects of magnetic field and inertia.
The Roland experiment is a means for charge on the nucleus producing a magnetic a field. If you haven’t heard of the Roland experiment, take a look at section 5 of this PDF:
Basically, Henry Rowland was a Hopkins university scientist who did experiments where he rotated a dielectric disc with charged conductive sectors and detected a magnetic field as a result of the rotating charge. So if the nucleus had enough rotational speed a magnetic field could result and if of sufficient strength could be a means for deflection of the solar wind.
There would need to be a large deflection of the solar wind so as to explain the appearance of decreased activity as well as the initial stretching out of the coma as in the case of what may have happened with comet Elenin. The deflection of charge could for example act in such a way so as to curve charge around the nucleus and concentrate the coma into an elongated shape.
Once a nucleus was sufficiently charged, I would like to propose that it not only stays charged but the electric or magnetic fields deflect the solar wind in such a way as the coma and or tails are unaffected and consequently do not show up much in normal observations. Also that, the nucleus continues to remain active via thermal interaction, but that gasses and dust remain near the nucleus until an event occurs that ignites one of the volatile gasses with oxygen liberated from water via UV degradation. The ignition could occur as a result of a meteoroid or asteroid impact or a superheated green house effect or other event that sufficiently heats any accumulated volatile gases to the ignition point.
Is there any direct evidence for this whatsoever? Nothing obvious that I can think of at this time. However, if come the beginning of October when we'll get a good look at comet Elenin with some of the larger telescopes in the Northern hemisphere and there is no visual sign of either a break up or disintegration, then we'll need to start thinking of some kind of CME related explanation. I did notice that the Hubble image of the inner coma of the comet Holmes outburst appears as an anisotropic hourglass shape.
This hourglass formation could be a result of charged ejecta material moving more readily along magnetic field lines as opposed to across magnetic field lines and something similar could have happened during the comet Holmes outburst.
Sometime tomorrow we will get a little more data from the NASA spacecraft SOHO when comet Elenin will move into its field of view. Then, three days later comet Elenin will be directly between the earth and the sun and will start to then move away from the sun allowing a view from earth. There is the possibility, if I'm correct in what I've proposed, that we could see a flareup of comet Elenin any time between now and the end of the year. If I am wrong, we will see with our most powerful telescopes that comet Elenin did in fact breakup and disintegrate, starting strangely at the same time the CME made contact with it.