Solar cycle 19
Encyclopedia
Solar cycle 19 is the nineteenth solar cycle
Solar cycle
The solar cycle, or the solar magnetic activity cycle, is a periodic change in the amount of irradiation from the Sun that is experienced on Earth. It has a period of about 11 years, and is one component of solar variation, the other being aperiodic fluctuations. Solar variation causes changes in...

 since 1755, when recording of solar sunspot
Sunspot
Sunspots are temporary phenomena on the photosphere of the Sun that appear visibly as dark spots compared to surrounding regions. They are caused by intense magnetic activity, which inhibits convection by an effect comparable to the eddy current brake, forming areas of reduced surface temperature....

activity began. The solar cycle lasted 10.5 years, beginning in April 1954 and ending in October 1964.

The maximum smoothed sunspot number (monthly number of sunspots averaged over a twelve month period) observed during the solar cycle was 201.3, and the minimum was 9.6.

There were a total of 227 days with no sunspots during this cycle.

Extreme events

Intense red aurora display frightened people in Europe on February 11, 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 November 13, 1960 and October 1, 1961.
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