The solar cycle or solar magnetic activity cycle is the nearly periodic 11-year change in the Sun's activity (including changes in the levels of solar radiation and ejection of solar material) and appearance (changes in the number of sunspots, flares, and other manifestations).
They have been observed (by changes in the sun's appearance and by changes seen on Earth, such as auroras) for centuries.
The changes on the sun cause effects in space, in the atmosphere, and on Earth's surface. While it is the dominant variable in solar activity, aperiodic fluctuations also occur.
Definition
Solar cycles have an average duration of about 11 years. Solar maximum and solar minimum refer respectively to periods of maximum and minimum sunspot counts. Cycles span from one minimum to the next.
Observational history
The solar cycle was discovered in 1843 by Samuel Heinrich Schwabe, who after 17 years of observations noticed a periodic variation in the average number of sunspots.Rudolf Wolf compiled and studied these and other observations, reconstructing the cycle back to 1745, eventually pushing these reconstructions to the earliest observations of sunspots by Galileo and contemporaries in the early seventeenth century.
The solar cycle is a 28-year cycle of the Julian calendar with respect to the week. It occurs because leap years occur every 4 years and there are 7 possible days to start a leap year, making a 28-year sequence.
This cycle also occurs in the Gregorian calendar, but it is interrupted by years such as 1700, 1800, 1900 and 2100, which are divisible by four but which are not leap years. This interruption has the effect of skipping 16 years of the solar cycle between February 28 and March 1. Because the Gregorian cycle of 400 years has exactly 146,097 days, i.e. exactly 20,871 weeks, one can say that the Gregorian so-called solar cycle lasts 400 years.
Calendar years are usually marked by Dominical letters indicating the first Sunday in a new year, thus the term solar cycle can also refer to a repeating sequence of Dominical letters.
Unless a year is not a leap year due to Gregorian exceptions, a sequence of calendars is reused every 28 years.
Solar cycle 14 was the fourteenth solar cycle since 1755, when extensive recording of solar sunspot activity began. The solar cycle lasted 11.5 years, beginning in February 1902 and ending in August 1913. The maximum smoothed sunspot number (monthly number of sunspots averaged over a twelve-month period) observed during the solar cycle was 64.2, in February 1906 (the lowest since the Dalton Minimum), and the minimum was 1.5. There were a total of approximately 1019 days with no sunspots during this cycle (the second highest recorded of any cycle to date).
Geomagnetic storms in November 1903, March 1905, and September 1909 affected telegraph lines.
NASA is a Swedishsynthpop band fronted by Patrik Henzel and Martin Thors. They debuted in 1983 with a song for a Swedish film. In 1985 they had a Swedish top ten hit "Paula". In the 1980s, the band had little success outside of Sweden. A planned US album was recorded, but then shelved by Columbia Records. They continued to have numerous hit singles in their home country of Sweden. They were basically defunct for most of the 1990s, but had a resurgence with the album "Remembering the Future" in 1999.
NASA 515 is a Boeing 737 heavily modified for NASA use as a continuing research facility. The aircraft was the first 737 built and was used by Boeing to qualify the 737 design. NASA 515 was maintained and flown by Langley Research Center as part of the Terminal Area Productivity (TAP) program.
The aircraft is on public display at the Museum of Flight, near Seattle, Washington.
Find out more about the NASA missions mentioned in this 2024 year-end highlight video by taking a deep dive with these resources.
Artemis Campaign: https://www.nasa.gov/specials/artemis/
Commercial Lunar Payload Services (CLPS): https://www.nasa.gov/commercial-lunar-
payload-services/
Crew Health and Performance Exploration Analog (CHAPEA):
https://www.nasa.gov/humans-in-space/chapea/
Ingenuity Mars Helicopter: https://www.jpl.nasa.gov/missions/ingenuity/
Artemis Accords: https://www.nasa.gov/artemis-accords/
2024 Total Eclipse: https://science.nasa.gov/eclipses/future-eclipses/eclipse-2024/
Commercial Crew: https://www.nasa.gov/humans-in-space/commercial-
space/commercial-crew-program/
International Space Station (ISS): https://www.nasa.gov/international-space-station/
PACE (Plankton, Ae...
published: 06 Dec 2024
NASA | Solar Cycle
The number of sunspots increases and decreases over time in a regular, approximately 11-year cycle, called the sunspot cycle. The exact length of the cycle can vary. It has been as short as eight years and as long as fourteen, but the number of sunspots always increases over time, and then returns to low again.
This video is public domain and can be downloaded at: http://svsdev.gsfc.nasa.gov/goto?10804
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f0004_index.html
Or find NASA Goddard Space Flight Center on Facebook:
http://www.facebook.com/NASA.GSFC
Or find us on Twitter:
http://twitter.com/NASAGoddard
Find out more about the NASA missions mentioned in this 2024 year-end highlight video by taking a deep dive with these resources.
Artemis Campaign: https://www...
Find out more about the NASA missions mentioned in this 2024 year-end highlight video by taking a deep dive with these resources.
Artemis Campaign: https://www.nasa.gov/specials/artemis/
Commercial Lunar Payload Services (CLPS): https://www.nasa.gov/commercial-lunar-
payload-services/
Crew Health and Performance Exploration Analog (CHAPEA):
https://www.nasa.gov/humans-in-space/chapea/
Ingenuity Mars Helicopter: https://www.jpl.nasa.gov/missions/ingenuity/
Artemis Accords: https://www.nasa.gov/artemis-accords/
2024 Total Eclipse: https://science.nasa.gov/eclipses/future-eclipses/eclipse-2024/
Commercial Crew: https://www.nasa.gov/humans-in-space/commercial-
space/commercial-crew-program/
International Space Station (ISS): https://www.nasa.gov/international-space-station/
PACE (Plankton, Aerosol, Cloud, ocean Ecosystem):
https://science.nasa.gov/mission/pace/
GOES Satellite Network: https://science.nasa.gov/mission/goes/
X-59 Quiet SuperSonic Aircraft: https://www.nasa.gov/specials/Quesst/
Solar Sail: https://www.nasa.gov/smallspacecraft/what-is-acs3/
James Webb Space Telescope: https://science.nasa.gov/mission/webb/
Europa Clipper: https://europa.nasa.gov/
Credit: NASA
Video Producer: Sonnet Apple
Music: Universal Production Music
Find out more about the NASA missions mentioned in this 2024 year-end highlight video by taking a deep dive with these resources.
Artemis Campaign: https://www.nasa.gov/specials/artemis/
Commercial Lunar Payload Services (CLPS): https://www.nasa.gov/commercial-lunar-
payload-services/
Crew Health and Performance Exploration Analog (CHAPEA):
https://www.nasa.gov/humans-in-space/chapea/
Ingenuity Mars Helicopter: https://www.jpl.nasa.gov/missions/ingenuity/
Artemis Accords: https://www.nasa.gov/artemis-accords/
2024 Total Eclipse: https://science.nasa.gov/eclipses/future-eclipses/eclipse-2024/
Commercial Crew: https://www.nasa.gov/humans-in-space/commercial-
space/commercial-crew-program/
International Space Station (ISS): https://www.nasa.gov/international-space-station/
PACE (Plankton, Aerosol, Cloud, ocean Ecosystem):
https://science.nasa.gov/mission/pace/
GOES Satellite Network: https://science.nasa.gov/mission/goes/
X-59 Quiet SuperSonic Aircraft: https://www.nasa.gov/specials/Quesst/
Solar Sail: https://www.nasa.gov/smallspacecraft/what-is-acs3/
James Webb Space Telescope: https://science.nasa.gov/mission/webb/
Europa Clipper: https://europa.nasa.gov/
Credit: NASA
Video Producer: Sonnet Apple
Music: Universal Production Music
The number of sunspots increases and decreases over time in a regular, approximately 11-year cycle, called the sunspot cycle. The exact length of the cycle can ...
The number of sunspots increases and decreases over time in a regular, approximately 11-year cycle, called the sunspot cycle. The exact length of the cycle can vary. It has been as short as eight years and as long as fourteen, but the number of sunspots always increases over time, and then returns to low again.
This video is public domain and can be downloaded at: http://svsdev.gsfc.nasa.gov/goto?10804
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f0004_index.html
Or find NASA Goddard Space Flight Center on Facebook:
http://www.facebook.com/NASA.GSFC
Or find us on Twitter:
http://twitter.com/NASAGoddard
The number of sunspots increases and decreases over time in a regular, approximately 11-year cycle, called the sunspot cycle. The exact length of the cycle can vary. It has been as short as eight years and as long as fourteen, but the number of sunspots always increases over time, and then returns to low again.
This video is public domain and can be downloaded at: http://svsdev.gsfc.nasa.gov/goto?10804
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f0004_index.html
Or find NASA Goddard Space Flight Center on Facebook:
http://www.facebook.com/NASA.GSFC
Or find us on Twitter:
http://twitter.com/NASAGoddard
Find out more about the NASA missions mentioned in this 2024 year-end highlight video by taking a deep dive with these resources.
Artemis Campaign: https://www.nasa.gov/specials/artemis/
Commercial Lunar Payload Services (CLPS): https://www.nasa.gov/commercial-lunar-
payload-services/
Crew Health and Performance Exploration Analog (CHAPEA):
https://www.nasa.gov/humans-in-space/chapea/
Ingenuity Mars Helicopter: https://www.jpl.nasa.gov/missions/ingenuity/
Artemis Accords: https://www.nasa.gov/artemis-accords/
2024 Total Eclipse: https://science.nasa.gov/eclipses/future-eclipses/eclipse-2024/
Commercial Crew: https://www.nasa.gov/humans-in-space/commercial-
space/commercial-crew-program/
International Space Station (ISS): https://www.nasa.gov/international-space-station/
PACE (Plankton, Aerosol, Cloud, ocean Ecosystem):
https://science.nasa.gov/mission/pace/
GOES Satellite Network: https://science.nasa.gov/mission/goes/
X-59 Quiet SuperSonic Aircraft: https://www.nasa.gov/specials/Quesst/
Solar Sail: https://www.nasa.gov/smallspacecraft/what-is-acs3/
James Webb Space Telescope: https://science.nasa.gov/mission/webb/
Europa Clipper: https://europa.nasa.gov/
Credit: NASA
Video Producer: Sonnet Apple
Music: Universal Production Music
The number of sunspots increases and decreases over time in a regular, approximately 11-year cycle, called the sunspot cycle. The exact length of the cycle can vary. It has been as short as eight years and as long as fourteen, but the number of sunspots always increases over time, and then returns to low again.
This video is public domain and can be downloaded at: http://svsdev.gsfc.nasa.gov/goto?10804
Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f0004_index.html
Or find NASA Goddard Space Flight Center on Facebook:
http://www.facebook.com/NASA.GSFC
Or find us on Twitter:
http://twitter.com/NASAGoddard
The solar cycle or solar magnetic activity cycle is the nearly periodic 11-year change in the Sun's activity (including changes in the levels of solar radiation and ejection of solar material) and appearance (changes in the number of sunspots, flares, and other manifestations).
They have been observed (by changes in the sun's appearance and by changes seen on Earth, such as auroras) for centuries.
The changes on the sun cause effects in space, in the atmosphere, and on Earth's surface. While it is the dominant variable in solar activity, aperiodic fluctuations also occur.
Definition
Solar cycles have an average duration of about 11 years. Solar maximum and solar minimum refer respectively to periods of maximum and minimum sunspot counts. Cycles span from one minimum to the next.
Observational history
The solar cycle was discovered in 1843 by Samuel Heinrich Schwabe, who after 17 years of observations noticed a periodic variation in the average number of sunspots.Rudolf Wolf compiled and studied these and other observations, reconstructing the cycle back to 1745, eventually pushing these reconstructions to the earliest observations of sunspots by Galileo and contemporaries in the early seventeenth century.