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How did the Maunder minimum relate to sunspot activity?

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Space weather Earth's full North Polar auroral oval, in an image taken in ultraviolet light by the U.S. Polar spacecraft over northern Canada, April 6, 1996. In the colour-coded image, which simultaneously shows dayside and nightside auroral activity, the most intense levels of activity are red, and the lowest levels are blue. Polar, launched in February 1996, was designed to further scientists' understanding of how plasma energy contained in the solar wind interacts with Earth's magnetosphere.

The Maunder minimum refers to a period between 1645 and 1715 characterized by a drastic and prolonged reduction in sunspot activity.1

While sunspot activity typically follows an 11-year cycle, the Maunder minimum represented a significant departure from this pattern. During this interval, astronomers observed very few sunspots, a phenomenon initially attributed by some to sporadic or poor observation techniques. However, later analysis of historical records and carbon-14 levels in tree rings confirmed that this was a genuine period of solar calm rather than a failure of observation. This era coincided with the coldest phase of the Little Ice Age, suggesting that even slight fluctuations in solar activity may influence Earth's climate, though the exact physical mechanism remains unknown.1