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theartist

A Solar Wind Phenomena rarely observed?

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Please kindly answer me, dear reader (should you choose):

  1. Do you see the phenomenon I'm trying to point out in the following animation?
  2. Have you ever seen that before?
  3. What is your explanation for it?

 

 

335287676_Windreverseflow.gif.2f9ef6c4d21ddebc941931ceaa27830b.gif

The phenomena occurs in the last half of the above animation.  

163548830_Windreverseflow.png.64f3091065fb0c445e6a0ef334ef978a.png

It gives the appearance of a 'reverse flow' running back toward the sun. In order to see it better, one can look at the animation directly at SOHO Movie Theater, inputting the time coordinates for the morning of 2019-10-10.

273543316_ScreenShot2019-10-15at9_56_05AM.thumb.png.c6dab204d963ca8709a9f3fd7b7bf0ec.png

Do the following two images, from the reference to the Hannes Alfvén paper provided in this thread, suggest what is going on?

1080075412_ScreenShot2019-10-15at9_59_39AM.png.d94196c7624cf75ca7df8a908a3ec27c.png1306836993_ScreenShot2019-10-15at9_59_49AM.png.3e526d52f5e6af6b132faf9122b76b2f.png

Edited by theartist

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Marcel, consider how many solar radii out the 'reverse flows' are. 

(BTW, videos, rather than GIFS, are much better in resolution quality and much easier to upload, and allow viewers to start/stop, and they actually are not much different in total memory size, so please consider allowing the upload of videos as in the past, yes?)

Also Marcel, although we have seen CME material collapse, have you ever seen this phenomena before in the coronagraph imagery, what appears like 'reverse flow' back against the outflowing solar wind?  

22 minutes ago, theartist said:

consider how many solar radii out the 'reverse flows' are. 

Marcel, thanks for prodding me to dig further; I just came upon this reference, which may provide an answer, and they admit inbound waves are not something commonly observed:

INBOUND WAVES IN THE SOLAR CORONA: A DIRECT INDICATOR OF ALFVÉN SURFACE LOCATION.

 

 

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2 uren geleden, theartist zei:

BTW, videos, rather than GIFS, are much better in resolution quality and much easier to upload, and allow viewers to start/stop, and they actually are not much different in total memory size, so please consider allowing the upload of videos as in the past, yes?

The videos has caused our monthly bill to rise to more than double. Gif’s are also relatively big in size and can further Increase the monthly billing. We disabled videos because of the increase in costs. We want to keep most of the features free to use so we have to take measures. 
 

apart from that... as you could see in the gif, there was some ejecta leaving the sun resulting in the magnetic field lines to open up into space and probably reconnect a bit later. But still the sun has magnetic field lines that are open into the interplanetary space and that gap in corona may look more dark when seen from that point of view. Just a guess ;) 

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This reminds me of other astrophysical effects. Pulsars have phenomena where some electrons and positrons confined by magnetic fields at lower latitudes flow out one side via the current sheet and eventually return back to the pulsar. That flow, aside from the gamma ray emissions that escape to space, return back and strike the pulsar. I believe this is both inside and outside the light cylinder. This is the generation mechanism of pulsar wind that leads to nebulae around pulsars such as Vela.

ill have to locate the paper when I get home, it’s also a lecture on YouTube at Cornell IIRC.

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I think both of you were getting the gist of what I think is going on, which is some magnetic reconnection effects causing inward (downward) flow of plasma on the outer regions of denser streamer formation, plasma that was previously at escape velocities outward. Coupled with the expected temperatures (probably at least 1 million K), and the apparent constant velocity of the flow (it didn't seem to be significantly accelerating inward), it is less likely due strictly to gravitation; it just looks atypical, counterintuitive, and something I had never noticed before in the C2 coronagraph.

A longer link of video clip (i.e., plus/minus one day centered around the event) is required to properly observe the phenomena in context, so that is why I was pointing the reader to the SOHO link so they can create their own higher-resolution video for observation.

Cheers.

Another point I wish to make is that here was a case where we actually get to see the inward flow of matter in the solar wind, but could it possibly be happening significantly, even though rarely observed optically?  Maybe the reverse flow of matter is significant enough to affect the surface flow of the photosphere plasma, and this is an out-of-the-box idea related to the one Hannes Alfvén was offering for an explanation of its apparent differential rotation

Edited by theartist

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