Solar cycle 2

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Solar cycle 2
Drawing of a sunspot from 1774, illustrating the Wilson effect
Sunspot data
Start dateJune 1766
End dateJune 1775
Duration (years)9
Max count193.0
Max count monthSeptember 1769
Min count18.6
Cycle chronology
Previous cycleSolar cycle 1 (1755–1766)
Next cycleSolar cycle 3 (1775–1784)

Solar cycle 2 was the second solar cycle since 1755, when extensive recording of sunspot activity began.[1][2] The solar cycle lasted 9 years, beginning in June 1766 and ending in June 1775. The maximum smoothed sunspot number observed during the solar cycle was 193.0 (September 1769), and the starting minimum was 18.6.[3]

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

See also[edit]


  1. ^ Kane, R.P. (2002), "Some Implications Using the Group Sunspot Number Reconstruction", Solar Physics, 205 (2): 383–401, Bibcode:2002SoPh..205..383K, doi:10.1023/A:1014296529097
  2. ^ "The Sun: Did You Say the Sun Has Spots?". Space Today Online. Retrieved 12 August 2010.
  3. ^ "SIDC Monthly Smoothed Sunspot Number".