List of solar cycles
From Wikipedia, the free encyclopedia
Here is the list of Solar cycles (or sunspot cycles), tracked since 1755:
- March 1755 - June 1766
- June 1766 - June 1775
- June 1775 - September 1784
- September 1784 - May 1798
- May 1798 - December 1810
- December 1810 - May 1823
- May 1823 - November 1833
- November 1833 - July 1843
- July 1843 - December 1855
- December 1855 - March 1867
- March 1867 - December 1878
- December 1878 - March 1890
- March 1890 - February 1902
- February 1902 - August 1913
- August 1913 - August 1923
- August 1923 - September 1933
- September 1933 - February 1944
- February 1944 - April 1954
- April 1954 - October 1964
- October 1964 - June 1976
- June 1976 - September 1986
- September 1986 - May 1996
- May 1996 - ongoing
- has not started, if we use same rules that have been used for the cycles 1-23
January: cycle 23: 1 spot group for 11 days, cycle 24: 1 spot group for 1 day
February: cycle 23: 1 spot group for 8 days, no cycle 24 spot groups
March-April: cycle 23: 8 spot groups for 49 days (some contemporaneous), cycle 24: 1 spot group in April for 2 days
Usually the change from cycle to cycle consists of 1-1.5 years time when there are spots from both old and new cycles.
The traditionally used breakpoint is when there is a takeover, although there are technics to separate minima out. The last time that cycles did not overlap was in 1810. 1809 contained only cycle 5 spots, 1810 was spotless, and 1811 contained only cycle 6 spots.
Numerous articles both in paper and net announced that cycle would have began as soon as the first spot in 4.1. appeared. That is not the convention used with cycles 1-23 and seems not valid, because the cycle 23 spots has still dominated the Sun.
The last word is said by an international conference of astronomers, who decide what the official minimum based on old rules and the apparent takeover of the new cycle is.
