The Dalton minimum in the 400-year history of sunspot numbers, showing the low peaks for solar cycles 5 and 6.
Solar cycle 5 was the fifth solar cycle since 1755, when extensive recording of solar sunspot activity began.[1][2] The solar cycle lasted 12.6 years, beginning in May 1798 and ending in December 1810 (thus falling within the Dalton Minimum). The maximum smoothed sunspot number (monthly number of sunspots averaged over a twelve-month period) observed during the solar cycle was 49.2, in February 1805 (the second lowest of any cycle to date, as a result of being part of the Dalton Minimum), and the minimum was zero.[3]
