--- id: 4e705b77-3bd5-448f-8eb5-c0d19d6aab9d title: 'Solar Cycle 11: Historical Overview and Sunspot Activity' abstract: This document provides a detailed overview of Solar Cycle 11, which occurred from March 1867 to December 1878. It details key metrics such as the cycle's duration of 11.8 years, a maximum smoothed sunspot number of 234.0 in August 1870, and a record-breaking 1,028 spotless days during the transition to the next cycle. The text also references historical observations of solar prominences and auroral displays associated with this period of solar activity. classification: primary: '52' secondary: - '524' - '537' udc_main_class: '5' tags: - solar cycle - sunspots - astronomy - solar activity - 19th century - space weather topics: - Astronomy - Solar Physics - Historical Science author: '' created_at: '2026-06-01T00:08:17.052154' updated_at: '2026-06-01T02:11:08.103640' sources: - type: url uri: https://en.wikipedia.org/wiki/Solar_cycle_11 format: url_fetch udc_label: Astronomy version: '1' --- ## Card: Solar Cycle 11: Historical Overview and Sunspot Activity This document provides a detailed overview of Solar Cycle 11, which occurred from March 1867 to December 1878. It details key metrics such as the cycle's duration of 11.8 years, a maximum smoothed sunspot number of 234.0 in August 1870, and a record-breaking 1,028 spotless days during the transition to the next cycle. The text also references historical observations of solar prominences and auroral displays associated with this period of solar activity. ## Classification Primary: 52 | Secondary: 524, 537 | Tags: solar cycle, sunspots, astronomy, solar activity, 19th century, space weather | Topics: Astronomy, Solar Physics, Historical Science ## Content Solar cycle 11 - Wikipedia Jump to content Main menu Main menu move to sidebar hide Navigation Main page Contents Current events Random article About Wikipedia Contact us Contribute Help Learn to edit Community portal Recent changes Upload file Special pages Search Search Appearance Donate Create account Log in Personal tools Donate Create account Log in Contents move to sidebar hide (Top) 1 See also 2 References 3 External links Toggle the table of contents Solar cycle 11 6 languages Français 日本語 Română தமிழ் Українська 中文 Edit links Article Talk English Read Edit View history Tools Tools move to sidebar hide Actions Read Edit View history General What links here Related changes Upload file Permanent link Page information Cite this page Get shortened URL Print/export Download as PDF Printable version In other projects Wikidata item Appearance move to sidebar hide From Wikipedia, the free encyclopedia Solar activity from March 1867 to December 1878 Solar cycle 11 Sunspots observed during solar cycle 11 (1873) Sunspot data Start date March 1867 End date December 1878 Duration (years) 11.8 Max count 234.0 Max count month August 1870 Min count 9.9 Spotless days 1028 Cycle chronology Previous cycle Solar cycle 10 (1855–1867) Next cycle Solar cycle 12 (1878–1890) Solar prominences observed by Carl Frederik Fearnley during solar cycle 11 (1872–1873). Solar cycle 11 was the eleventh solar cycle since 1755, when extensive recording of solar sunspot activity began. [ 1 ] [ 2 ] The solar cycle lasted 11.8 years, beginning in March 1867 and ending in December 1878. The maximum smoothed sunspot number observed during the solar cycle was 234.0 (August 1870), and the starting minimum was 9.9. [ 3 ] During the minimum transit from solar cycle 11 to 12, there were a total of 1028 days with no sunspots (the highest recorded of any cycle transit to date). [ 4 ] [ 5 ] [ 6 ] Strong auroral displays were observed in October 1870, February 1872, and August 1872. [ 7 ] See also [ edit ] List of solar cycles References [ edit ] ^ 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 ^ "The Sun: Did You Say the Sun Has Spots?" . Space Today Online . Retrieved 12 August 2010 . ^ SIDC Monthly Smoothed Sunspot Number. " [1] " ^ Spotless Days. " [2] " ^ Dr. Tony Phillips (11 July 2008). "What's Wrong with the Sun? (Nothing)" . NASA. Archived from the original on 14 July 2008. ^ Solaemon's Spotless Days Page. " [3] " ^ Storms, Solar (28 July 2017). "Space Weather Newspaper Archives" . www.solarstorms.org . External links [ edit ] SIDC formula v t e Solar cycles 18th century 1740–1759 Solar cycle 1 (1755 Feb – 1766 Jun) 1760–1779 Solar cycle 2 (1766 Jun – 1775 Jun) Solar cycle 3 (1775 Jun – 1784 Sep) 1780–1799 Solar cycle 4 (1784 Sep – 1798 Apr) Solar cycle 5 (1798 Apr – 1810 Aug) 19th century 1800–1819 Solar cycle 6 (1810 Aug – 1823 May) 1820–1839 Solar cycle 7 (1823 May – 1833 Nov) Solar cycle 8 (1833 Nov – 1843 Jul) 1840–1859 Solar cycle 9 (1843 Jul – 1855 Dec) Solar cycle 10 (1855 Dec – 1867 Mar) 1860–1879 Solar cycle 11 (1867 Mar – 1878 Dec) Solar cycle 12 (1878 Dec – 1890 Mar) 1880–1899 Solar cycle 13 (1890 Mar – 1902 Jan) 20th century 1900–1919 Solar cycle 14 (1902 Jan – 1913 Jul) Solar cycle 15 (1913 Jul – 1923 Aug) 1920–1939 Solar cycle 16 (1923 Aug – 1933 Sep) Solar cycle 17 (1933 Sep – 1944 Feb) 1940–1959 Solar cycle 18 (1944 Feb – 1954 Apr) Solar cycle 19 (1954 Apr – 1964 Oct) 1960–1979 Solar cycle 20 (1964 Oct – 1976 Mar) Solar cycle 21 (1976 Mar – 1986 Sep) 1980–1999 Solar cycle 22 (1986 Sep – 1996 Aug) Solar cycle 23 (1996 Aug – 2008 Dec) 21st century 2000–2019 Solar cycle 24 (2008 Dec – 2019 Dec) Solar cycle 25 (2019 Dec – present) List of solar cycles List of solar storms List of solar maxima and minima Portals : Astronomy Stars Spaceflight Outer space Solar System This article related to the Sun is a stub . You can help Wikipedia by adding missing information . v t e Retrieved from " https://en.wikipedia.org/w/index.php?title=Solar_cycle_11&oldid=1104752694 " Categories : Solar cycles Sun stubs Hidden categories: Articles with short description Short description matches Wikidata Use dmy dates from September 2019 All stub articles This page was last edited on 16 August 2022, at 18:20  (UTC) . Text is available under the Creative Commons Attribution-ShareAlike 4.0 License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy . Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc. , a non-profit organization. Privacy policy About Wikipedia Disclaimers Contact Wikipedia Legal & safety contacts Code of Conduct Developers Statistics Cookie statement Mobile view Search Search Toggle the table of contents Solar cycle 11 6 languages Add topic ## Source - url: https://en.wikipedia.org/wiki/Solar_cycle_11