# Gravitational/electromagnetic effect of planets on solar activity?

Does the gravitational and/or electromagnetic influence of planets have any effect or correspondence to solar activities (e.g. solar flares/CMEs) - and if so, does the planetary position (where they are in their orbit in regards to distance from the sun) have an effect? How do we know?

• It is a curious coincidence(?) that the solar activity cycle is about the orbital period of Jupiter... – Rob Jeffries Oct 28 '18 at 20:42
• Wow, yes it appears to be very close. Interesting. – Ben Linzmeier Oct 28 '18 at 21:55

For example Stefani et al. (2016) have done some theoretical work, claiming that the 11.07 year cycle with which the tidal effects of Jupiter, the Earth and Venus line up, might excite a resonance in the $$\alpha$$ part of the $$\alpha-\Omega$$ dynamo. This resonance could lead to the solar magnetic cycle.