Solar cycle 11was the eleventhsolar cyclesince 1755, when extensive recording of solarsunspotactivity began.[1][2]The solar cycle lasted 11.8 years, beginning in March 1867 and ending in December 1878. The maximumsmoothed sunspot numberobserved 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]
