I was teaching the physics of lunar tides. And it occurred to me to look and see if the planets have an effect on the “solar tides”. If the moon can pull on the oceans, why can’t Jupiter, Venus, Earth, and Mercury do the same to the sun. The sunspot cycle is nearly the same as Jupiter’s orbital period.
Well, sure enough, NASA has a research study showing that the planets do indeed affect solar activity. The probability of this randomly happening is 0.039%
This goes back to the age-old assertion that the sun and the planets are the cause of climate variability.
See: Apparent Relations Between Solar Activity and Solar Tides Caused by the Planets
Abstract:
A solar storm is a storm of ions and electrons from the Sun. Large solar storms are usually preceded by solar flares, phenomena that can be characterized quantitatively from Earth. Twenty-five of the thirty-eight largest known solar flares were observed to start when one or more tide-producing planets (Mercury, Venus, Earth, and Jupiter) were either nearly above the event positions (less than 10 deg. longitude) or at the opposing side of the Sun. The probability for this to happen at random is 0.039 percent. This supports the hypothesis that the force or momentum balance (between the solar atmospheric pressure, the gravity field, and magnetic field) on plasma in the looping magnetic field lines in solar corona could be disturbed by tides, resulting in magnetic field reconnection, solar flares, and solar storms. Separately, from the daily position data of Venus, Earth, and Jupiter, an 11-year planet alignment cycle is observed to approximately match the sunspot cycle. This observation supports the hypothesis that the resonance and beat between the solar tide cycle and nontidal solar activity cycle influences the sunspot cycle and its varying magnitudes. The above relations between the unpredictable solar flares and the predictable solar tidal effects could be used and further developed to forecast the dangerous space weather and therefore reduce its destructive power against the humans in space and satellites controlling mobile phones and global positioning satellite (GPS) systems.