Solar cycle 19

{{Infobox Solar cycles

|image=Prot19590411 0918.png

|caption=A solar prominence during solar cycle 19 (11 April 1959).

|cycle_num=19

|start_date=April 1954

|end_date=October 1964

|duration=10.5

|max_count=285.0

|max_count_date=March 1958

|min_count=5.1

|spotless_count=227

|prev_name=Solar cycle 18

|next_name=Solar cycle 20

|prev_dates=1944–1954

|next_dates=1964–1976

}}

Solar cycle 19 was the nineteenth solar cycle since 1755, when extensive recording of solar sunspot activity began.{{citation|doi=10.1023/A:1014296529097|year=2002|last1=Kane|first1=R.P.|title=Some Implications Using the Group Sunspot Number Reconstruction|journal=Solar Physics|volume=205|issue=2|pages=383–401|bibcode=2002SoPh..205..383K}}{{cite web | title=The Sun: Did You Say the Sun Has Spots? | url=http://www.spacetoday.org/SolSys/Sun/Sunspots.html | publisher=Space Today Online | accessdate=12 August 2010}} 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.

The maximum smoothed sunspot number observed during the solar cycle was 285.0, in March 1958 (the highest on record{{cite journal |last1=Dodson |first1=Helen W. |last2=Hedeman |first2=E. Ruth |last3=Mohler |first3=Orren C. |date=August 1974 |title=Comparison of activity in solar cycles 18, 19, and 20 |journal=Reviews of Geophysics |volume=12 |issue=3 |pages=329–341 |doi=10.1029/RG012i003p00329 |bibcode = 1974RvGSP..12..329D }}), and the starting minimum was 5.1.SIDC Monthly Smoothed Sunspot Number. "[http://sidc.oma.be/sunspot-data/]"

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.Spotless Days. "[http://spaceweather.com/glossary/spotlessdays.htm?PHPSESSID=dli444kmrjgre0rjq6l86fv144]"{{cite web |url=https://science.nasa.gov/headlines/y2008/11jul_solarcycleupdate.htm|archive-url=https://web.archive.org/web/20080714032353/https://science.nasa.gov/headlines/y2008/11jul_solarcycleupdate.htm|url-status=dead|archive-date=14 July 2008|title=What's Wrong with the Sun? (Nothing)|date=11 July 2008|author=Dr. Tony Phillips|publisher=NASA}}Solaemon's Spotless Days Page. "[http://users.telenet.be/j.janssens/Spotless/Spotless.html]"