1
$\begingroup$

It's my understanding that the mechanism behind Coronal Heating - why the Corona is so much hotter (> 1,000,000 K) than the surface of the Sun (6,000 K), and the mechanism by which the energy gets from the surface to the corona - is still very much an open question. I had an idea today that I wanted to get some information on.

It is also my understanding that Rubin's work on Dark Matter explained the uncharacteristic velocity distribution of spiral galaxies by calculating what the distribution would be with Dark Matter distributed toward the outer edge of the galaxy.

I was wondering, would a similar presence of Dark Matter around the sun (distributed toward the outer edge of the Sun) be a possible explanation for why the solar corona is so much hotter than the surface?

$\endgroup$
  • 1
    $\begingroup$ How exactly would this work? Rubin's idea of dark matter was simply to explain the missing mass in the galaxies. $\endgroup$ – HDE 226868 Aug 18 '14 at 19:26
  • 1
    $\begingroup$ Coronal heating is a lot better understood today, than in the past, it has basically moved from an open problem to one that is complex, but tractable. I do not believe that an external source of energy was needed at any time to explain the temperature rise in this very hot, but low density plasma. The problem is simply one of modeling the coupling and timescales of solar magnetic fields to a very complex and dynamic layer of the sun's atmosphere. This article explains some of the current thinking:arxiv.org/abs/1206.6097 $\endgroup$ – CuriousOne Aug 18 '14 at 19:36
  • $\begingroup$ Nice paper, @CuriousOne. $\endgroup$ – HDE 226868 Aug 18 '14 at 21:05
  • 1
    $\begingroup$ Why the votes to close? This is a perfectly reasonable question. $\endgroup$ – John Rennie Aug 19 '14 at 5:19
  • 2
    $\begingroup$ @brightmagus: to be fair, there are lots and lots of duplicates and basically silly questions that the reviewers have to sift through in an attempt to keep standards at a reasonable level. If they occasionally get trigger happy I find it hard to condemn them for it. The appropriate response is to answer the question and thereby demonstrate that it's a question worth answering. $\endgroup$ – John Rennie Aug 19 '14 at 6:32
1
$\begingroup$

For a potential dark matter cloud around the Sun to affect the corona you would have to propose a mechanism. The most obvious one would be for dark matter particles to transfer energy to corona particles, but dark matter interacts with ordinary matter far too weakly for this to happen.

$\endgroup$
  • $\begingroup$ Couldn't you make the same argument for the spiral galaxies then, though? My thinking was just that if dark matter can gather in distributions that affect the speed at which whole planets and bodies orbit around galaxies, you should be able to generate a distribution of matter around the sun that the interaction (gravitational - though I know it's very weak- or, in the case of WIMPs, even Weak) with the particles in the corona could cause massive temperature differences. Perhaps this distribution (greater density further from the center of normal matter concentration) is characteristic of DM $\endgroup$ – D. W. Aug 19 '14 at 18:45
  • $\begingroup$ @D.W. It doesn't "gather", itstayswidely distributed and this why it can affect the rotation curves via gravitational interaction. What mechanism heats a corona by gravitational interactions? The density of dark matter decreases with distance from the centre of galaxies. $\endgroup$ – Rob Jeffries May 11 '18 at 6:58
0
$\begingroup$

A recent post on astro-ph (Monday 7 2018, 'Solar Corona Heating by the Axion Quark Nugget Dark Matter') says that your suggestion is correct. The article explains how axion quark nuggets of dark matter falling onto the sun provide the exact amount of energy necessary to heat the corona and also predict the position of the transition region. If you do a search on Axion Quark Nuggets, you will see the many applications of that type of dark matter (solar flares, 21 cm absorption line, etc). There were several findings in the last two years.

$\endgroup$
  • $\begingroup$ This is a little light on details. Could you add more information? $\endgroup$ – Chris May 11 '18 at 4:42

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.