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arXiv · 2311.08317

Do the planets cause the sunspot cycles?

Abstract

The mainstream dynamo models predict that the sunspot cycle is non-stationary and stochastic. The official Solar Cycle Prediction Panel forecasts only the ongoing sunspot cycle because any forecast beyond one cycle is considered impossible. We analyse the sunspot data using our Discrete Chi-square Method (DCM). This method can detect many periodic signal superimposed on an arbitrary trend. We detect the extremely significant strong 10, 11, and 11.86 years signals. The Discrete Fourier Transform (DFT) cross-check confirms that these signals are certainly real. The interference of the 10 and 11 years signals ca cause the detected long 110 years signal in real data. Long periods or interference can never appear in simulated non-stationary stochastic sunspot data. We detect long periods and interference in the real data. Our deterministic DCM model predictions are more accurate and longer than the official Solar Cycle Prediction Panel forecast. The DCM models can predict the past prolonged activity minima, like the Maunder minimum era, although we do not have data from these periods. We claim that the sunspot data are stationary and multi-periodic, and therefore deterministic. We connect the detected signals to the orbital periods of Mercury, Venus, the Earth and Jupiter. If the planets cause the sunspot cycle, the exoplanets may cause the starspot cycles observed in other chromospherically active stars.

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Lauri Jetsu. 2025-08-13. Do the planets cause the sunspot cycles?. https://arxiv.org/abs/2311.08317

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