I was reading a popular news account of the sun's upcoming magnetic field reversal at http://www.csmonitor.com/Science/2013/0807/Sun-s-magnetic-reversal-means-big-changes-for-the-solar-system-video, and was confused already in the second paragraph:

Data from NASA-supported observatories indicate that the next flip will happen in just three to four months – the north pole has already jumped the gun and reversed, and scientists are now just waiting for the south pole to catch-up. The completed flip will herald changes throughout the entire solar system, according to a NASA video.

This doesn't make any sense to me. Given that there are no magnetic monopoles, there is no way for the sun to have two "south" magnetic poles. The field lines have to close somehow. (Granted, I don't for the life of me understand what a flux rope is, although the videos are cool.) I conclude that one of the following must be true:

  1. Most likely: the reporter misinterpreted / mistranslated-into-colloquial something a scientist said.
  2. Reasonably likely: my understanding of magnetism is completely wrong.
  3. Unlikely: all of the known physics of magnetism is completely wrong.

The reason I think 3. is unlikely is that it would have been the headline, not "Sun's magnetic reversal..."

So which is it? More generally, if it's possible to give a somewhat-technical description of "Sun's magnetic reversal", that would be awesome (but I realize that most likely that would require a book chapter, and is outside the scope of this forum). Feel free to gear your answer at the level of an incoming physics PhD student.

  • $\begingroup$ Welcome to physics.SE. I've deleted some material from the question that was chatty or apologetic -- this kind of thing is discouraged on SE. $\endgroup$
    – user4552
    Aug 10, 2013 at 1:25

1 Answer 1


The news release from NASA does mention this. Apparently in this transitional phase the field is not well represented as a dipolar field. Right now it may be a Quadra polar or higher (even numbered) field. Think of the total field being the superposition of multiple non-axial non-centered dipoles. The field is weakening in intensity too and may become weaker still before it strengthens into a reversed dipole field.

  • $\begingroup$ +1 I would only add the (nearly trivial) observation that a more chaotic field need not be symmetric in any way - there can be a strongly concentrated inward flux in one part of the surface with all the outward flux being rather diffuse on a bigger patch, just so long as the surface integral of the normal component is 0. $\endgroup$
    – user10851
    Aug 10, 2013 at 7:41

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