Not only the very concise 11-year cycle, but also all other periodic fluctuations in the sun's activity can be timed by the gravitational forces of the planets. A team from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and the Institute of Continuous Media Mechanics in Perm, Russia, is using new model calculations to propose a comprehensive explanation of all important known solar cycles.
They expose the longest fluctuations in activity over thousands of years as a chaotic process. Satisfactory explanations for the many cyclical, overlapping fluctuations in the sun's activity have long been sought worldwide. In addition to the best-known, approximately eleven-year "Schwabe cycle", the sun also exhibits longer fluctuations of hundreds to thousands of years. Why the magnetic field changes at all, however, is the subject of widely differing explanations and models among experts. Do planets possibly play a role as a "metronome" for solar activity?
The effect of tidal forces on the solar dynamo is strongest when the planets are aligned: A constellation that occurs every 11.07 years. This would already explain the 11-year cycle due to the influence of the planets. Longer-term forecasts of solar activity, such as its influence on climate developments, will, however, hardly be possible in principle, as the system will then tip over into chaos due to mathematical random processes and take a while to get back into sync.
