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I saw these figures and could not get why the magnetic field lines are not pointing from the north pole towards the south pole but they do the opposite.

enter image description here

Or also this picture which is about magnetic characteristics of the sun says the same thing:

enter image description here

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That was a curiosity that I also had once. The reason for that is that the magnetic pole near earth's geographic north pole is actually the south magnetic pole. You can find a more detailed answer on https://wtamu.edu/~cbaird/sq/2013/11/15/why-does-a-magnetic-compass-point-to-the-geographic-north-pole/

Happy Thanksgiving!

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    $\begingroup$ This is only half the answer, given that the question also asks about the Sun. The full answer is (presumably - I’m not an expert on this) that the convention is to show the direction of magnetic flux from the nominated south magnetic pole to nominated north magnetic pole. $\endgroup$ Nov 28, 2019 at 23:21
  • $\begingroup$ @ChappoSaysReinstateMonica lol, I actually forgot that part of the question... Thanks for pointning out. $\endgroup$
    – muyustan
    Nov 28, 2019 at 23:35
  • $\begingroup$ @ChappoHasn'tForgottenMonica: That's not the convention at all. The convention is north to south, like everywhere else. That image simply has gotten that convention wrong, and sadly has been reused in a ton of different places since it was published. $\endgroup$
    – Outis Nemo
    Jan 24 at 10:16
  • $\begingroup$ @OutisNemo yes, you're absolutely correct. If I'd spent a few seconds looking up magnetic polarity, I'd have learnt that the "magnetic field lines of a magnet are considered by convention to emerge from the magnet's north pole and reenter at the south pole" (my italics). Your own answer now provides the missing half of the clarification the OP was seeking. :-) $\endgroup$ Jan 27 at 2:49
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As someone already answered, the Earth part is due to the fact that the north magnetic pole is actually the one situated near the south geographic pole.

As for the Sun on the other hand, it's simply that image which is wrong, and not following convention; the convention is for positive spots to be labeled north, i.e. for field lines to go from north to south, just like is the convention in magnetism in general.

The reason for this confusion is that sunspots aren't typically actually labeled "north" or "south" at all like on a bar magnet, but rather as "positive" ("outward") and "negative" ("inward"). In many texts you can however indeed see references to the spots as "north-seeking" or "south-seeking", such as here:

Bear in mind that magnets always have a north pole and a south pole. Whenever sunspots are observed in pairs, or in groups containing two principal spots, one of the spots usually has the magnetic polarity of a north-seeking magnetic pole and the other has the opposite polarity.

This is ironically because "north-seeking" means "seeking geographic north here on Earth", which as mentioned above is actually the south magnetic pole; this is defined as the north pole of a magnet, and as such the north pole of a magnet is uniquely determined by which polarity is "north-seeking", which is the one where field lines are positive and extend outward, just like on a bar magnet.

Of course, just like you can technically say the field lines go from south to north inside a bar magnet, you could also look at sunspots from underneath the surface and see that it'd be flipped (since magnetic field lines always form loops due to Gauss's law for magnetism), but since we as humans always observe bar magnets and the Solar surface from the outside, what is north and south is thus uniquely defined by looking at the direction of the field lines on this side of the closed surface (the outside).

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    $\begingroup$ Thanks Outis for posting this addition. However, without any references, we can only take this information at face value; as you yourself note in a comment on the other answer, people can get their facts wrong. This would be a much better answer if you edit it to add a link to an authoritative source that supports your statement about the convention for direction of field lines. I'd be happy to upvote your answer if it included such a reference. $\endgroup$ Jan 25 at 23:35
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    $\begingroup$ Sure thing; I added a reference and explained in a bit more detail now. $\endgroup$
    – Outis Nemo
    Jan 26 at 13:29

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