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Prograde means rotating in the same direction in which most of the planets in our solar system rotate, which is counterclockwise, and retrograde rotation means the opposite, i.e., clockwise rotation. I do not remember the source, but somewhere I had read that Sun continues shifting between prograde and retrograde rotation. The rotation will be prograde for a particular period of the interval; after that, it will be retrograde and then again prograde. I do not remember exactly where I had read this. But now, when I search on google if this is true, I am not getting any relevant information. Now I doubt whether this is indeed true or not. Can someone help me with this?

Note: I am talking about retrograde rotation, not retrograde orbit.

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That does not happen. That cannot happen on grounds of conservation of angular momentum.

You might confuse this with a text talking about the Sun's magnetic field which undergoes a constant change and reverses polarity roughly every 11 years. You do see this cycle in magnetic activity easily by means of number of Sunspots and where they occur on the Sun.

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    $\begingroup$ A minor nit: you can conserve AngMomentum and reverse the rotation relative to the planetary planne by rotating the sun's axis of rotation 180 degrees. (You'd have to have a little bit of angular momentum in that plane, of course). $\endgroup$
    – Carl Witthoft
    Aug 8, 2022 at 14:43
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    $\begingroup$ @CarlWitthoft no, you can't. Any change in the axis of rotation is a change in angular momentum, it can only be done by exchanging momentum with some other object. $\endgroup$
    – Christopher James Huff
    Aug 8, 2022 at 16:50
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    $\begingroup$ @ChristopherJamesHuff But if you start out with some angmom on that axis, it remains. Granted that probably leads to a smooth continuous precession of the main polar axis. $\endgroup$
    – Carl Witthoft
    Aug 8, 2022 at 17:32
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    $\begingroup$ Effects like the Dzhanibekov effect depend on radically different moments of inertia along different axes that can transfer the angular momentum. Note that the rotation direction is still the same relative to the external universe, just the physical orientation of the object has inverted and is thus locally spinning the "other way". In no way would this result in the object shifting from prograde to retrograde, which are external measures of direction. $\endgroup$
    – throx
    Aug 9, 2022 at 0:05
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    $\begingroup$ @Beanluc the axis of rotation is not changing in that video. $\endgroup$
    – Christopher James Huff
    Aug 9, 2022 at 17:47

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