Solar cycle 2

Solar cycle 2
Drawing of a sunspot from 1774, illustrating the Wilson effect
Sunspot data
Start date	June 1766
End date	June 1775
Duration (years)	9
Max count	193.0
Max count month	September 1769
Min count	18.6
Cycle chronology
Previous cycle	Solar cycle 1 (1755-1766)
Next cycle	Solar cycle 3 (1775-1784)

Solar cycle 2 was the second solar cycle since 1755, when extensive recording of solar sunspot activity began. The solar cycle lasted 9 years, beginning in June 1766 and ending in June 1775. The maximum smoothed sunspot number (SIDC formula) observed during the solar cycle was 193.0 (September 1769), and the starting minimum was 18.6.

Sunspot observations by Alexander Wilson during this period established the Wilson effect.