Solar cycle 18 was the eighteenth solar cycle since 1755, when extensive recording of solar sunspot activity began.[1][2] The solar cycle lasted 10.2 years, beginning in February 1944 and ending in April 1954. The maximum smoothed sunspot number observed during the solar cycle was 218.7 (May 1947), and the starting minimum was 12.9.[3] During the minimum transit from solar cycle 18 to 19, there were a total of 446 days with no sunspots.[4][5][6]
Cycle 18 was characterized by "giant" sunspots.[7] The recording of the 10.7 cm (2800 MHz) solar radio flux began partway during this cycle,[8] and values of the solar flux during this cycle turned out to be particularly high.[7]
^Kane, R.P. (2002), "Some Implications Using the Group Sunspot Number Reconstruction", Solar Physics, 205 (2): 383–401, Bibcode:2002SoPh..205..383K, doi:10.1023/A:1014296529097, S2CID 118144552
^"The Sun: Did You Say the Sun Has Spots?". Space Today Online. Retrieved 12 August 2010.
^SIDC Monthly Smoothed Sunspot Number. "[1]"
^Spotless Days. "[2]"
^Dr. Tony Phillips (11 July 2008). "What's Wrong with the Sun? (Nothing)". NASA. Archived from the original on 14 July 2008.
^Solaemon's Spotless Days Page. "[3]"
^ abDodson, Helen W.; Hedeman, E. Ruth; Mohler, Orren C. (August 1974). "Comparison of activity in solar cycles 18, 19, and 20". Reviews of Geophysics. 12 (3): 329–341. Bibcode:1974RvGSP..12..329D. doi:10.1029/RG012i003p00329.
^Petersen, Edward (2012). Single Event Effects in Aerospace. Wiley. p. 20. ISBN 978-1118084304.
The solarcycle, also known as the solar magnetic activity cycle, sunspot cycle, or Schwabe cycle, is a nearly periodic 11-year change in the Sun's activity...
Solarcycles are nearly periodic 11-year changes in the Sun's activity that are based on the number of sunspots present on the Sun's surface. The first...
Solarcycle 25 is the current solarcycle, the 25th since 1755, when extensive recording of solar sunspot activity began. It began in December 2019 with...
Solarcycle 23 was the 23rd solarcycle since 1755, when extensive recording of solar sunspot activity began. The solarcycle lasted 12.3 years, beginning...
Solarcycle 2 was the second solarcycle since 1755, when extensive recording of sunspot activity began. The solarcycle lasted 9 years, beginning in June...
secondary steam cycle will warm up, improving fuel efficiency and providing further power. In November 2013, the Fraunhofer Institute for Solar Energy Systems...
geomagnetic storm components that occurred from 10–13 May 2024 during solarcycle 25. The geomagnetic storm was the most powerful to affect Earth since...
in divine years (years of the gods), each lasting for 360 solar (human) years. Each Yuga Cycle lasts for 4,320,000 years (12,000 divine years) with its...
(PDF) on 2009-03-18. Retrieved 2009-03-17. Batton, Bill (2000-06-18). "Organic Rankine Cycle Engines for Solar Power" (PDF). Solar 2000 conference. Barber-Nichols...
alternate between lunar and solar with each cycle, occurring at the same node and with similar characteristics. A solar eclipse with small gamma will...
from the original on 18 July 2009. Riley, P.; Linker, J. A.; Mikić, Z. (2002). "Modeling the heliospheric current sheet: Solarcycle variations". Journal...
solar eclipse can only be viewed from a relatively small area of the world. As such, although total solar eclipses occur somewhere on Earth every 18 months...
Irradiance in space is a function of distance from the Sun, the solarcycle, and cross-cycle changes. Irradiance on the Earth's surface additionally depends...
monthly cycles of the Moon's phases (synodic months, lunations), in contrast to solar calendars, whose annual cycles are based on the solar year. The...
Concentrated solar power (CSP, also known as concentrating solar power, concentrated solar thermal) systems generate solar power by using mirrors or lenses...
ejections, solar particle events, and other eruptive solar phenomena. The occurrence of solar flares varies with the 11-year solarcycle. Solar flares are...
being 1.361 kilowatts per square meter (kW/m2) at solar minimum (the time in the 11-year solarcycle when the number of sunspots is minimal) and approximately...
geomagnetic storm in recorded history, peaking on 1–2 September 1859 during solarcycle 10. It created strong auroral displays that were reported globally and...
Solar flare § Soft X-ray classification). The following table lists the largest flares in this respect since June 1996, the beginning of solarcycle 23...
Solar power, also known as solar electricity, is the conversion of energy from sunlight into electricity, either directly using photovoltaics (PV) or indirectly...
polarity. Their number varies according to the approximately 11-year solarcycle. Individual sunspots or groups of sunspots may last anywhere from a few...
The Solar Hijri calendar is the official calendar of Iran. It is a solar calendar and is the one Iranian calendar that is the most similar to the Gregorian...
Saros cycle series 116 for solar eclipses occurred at the Moon's descending node, repeating every 18 years, 11 days, containing 70 eclipses, 53 of which...
Global Information