evidence: The most famous example of this is the Maunder minimum, which saw seven decades of freezing weather, began in 1645 and lasted through to 1715, and happened when sunspots were exceedingly rare. [...] Now, scientists are concerned that we could face another prolonged solar minimum again. [...] The researchers stated in the study published in the journal Nature: "Recently discovered long-term oscillations of the solar background magnetic field associated with double dynamo waves generated in inner and outer layers of the Sun indicate that the solar activity is heading in the next three decades (2019–2055) to a Modern grand minimum similar to Maunder one."