Top 32 largest sunspots

The usual way of measuring the size of a sunspot group is to express the area it covers in “millionths”. A sunspot that covers 1 millionth would cover 0.000001 times the area of the Sun’s Earth-facing hemisphere. For a sunspot (or sunspot group) to be visible to the protected naked eye it must cover about 300 to 500 millionths or more (by comparison, the Earth would cover 169 millionths). This list shows all the sunspots/sunspot groups that have been visible since 1874 and were larger than AR2192.

 

 Year:  Month:  Day:  AR No.:  Sunspot Area (in millionths):
 1892  February 10  2421  2038
 1905  February 2  5441  3339
 1905  October 19  5682  2995
 1917  February 14  7977  3590
 1917  August 9  8181  3178
 1925  December 22  9830  2934
 1926  January 19  9861  3716
 1937  July 28  12455  3303
 1937  October 5  12553  3340
 1938  January 12  12673  3627
 1938  July 20  12902  3379
 1938  October 12  13024  3003
 1939  September 5  13394  3054
 1939  September 13  13405  2993
 1940  January 6  13502  2860
 1941  September 21  13937  3088
 1946  February 7  14417  5202
 1946  July 29  14585  4720
 1947  February 10  14813  2944
 1947  March 5  14851  4554
 1947  April 3  14886  6132 (largest in recent history)
 1950  February 15  16410  2856
 1951  May 19  16763  4865
 1959  January 8  19109  2805
 1968  February 1  21482  3202
 1982  June 14  3776  3100
 1982  July 12  3804  2870
 1988  June 29  5060  2900
 1989  March 17  5395  3600
 1989  August 29  5669  3080
 1990  November 18  6368  3080
 2014  October 27  2192  2790

Sources: Data taken from Spaceweather.com & Spaceweatherlive.com websites.

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