Solar cycle 19 was the nineteenth solar cycle since 1755, when extensive recording of solar sunspot activity began.[1][2] The solar cycle lasted 10.5 years, beginning in April 1954 and ending in October 1964. The International Geophysical Year occurred at the peak of this solar cycle.
Solar cycle 19 | |
---|---|
Sunspot data | |
Start date | April 1954 |
End date | October 1964 |
Duration (years) | 10.5 |
Max count | 285.0 |
Max count month | March 1958 |
Min count | 5.1 |
Spotless days | 227 |
Cycle chronology | |
Previous cycle | Solar cycle 18 (1944–1954) |
Next cycle | Solar cycle 20 (1964–1976) |
The maximum smoothed sunspot number observed during the solar cycle was 285.0, in March 1958 (the highest on record[3]), and the starting minimum was 5.1.[4]
During the minimum transit from solar cycle 19 to 20, there were a total of 227 days with no sunspots. This was the lowest number since 1850.[5][6][7]
A geomagnetic storm in February 1956 interfered with radio communications and prompted a search for the British submarine Acheron after it lost radio contact.[8]
Intense red aurora displays frightened people in Europe on 11 February 1958 and were visible from many US cities as far south as the 40th parallel. This geomagnetic storm caused a radio blackout over North America.
Aurora displays were visible over New York on 13 November 1960 and 1 October 1961.[9]