Spörer's law predicts the variation of
sunspot latitudes during a
solar cycle
The solar cycle, 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 measured in terms of variations in the number of observed sunspots on the Sun's surfa ...
. It was discovered by the English astronomer
Richard Christopher Carrington around 1861. Carrington's work was refined by the German astronomer
Gustav Spörer.
At the start of a sunspot cycle, sunspots tend to appear around 30° to 45° latitude on the
Sun's surface. As the cycle progresses, sunspots appear at lower and lower latitudes, until they average 15° at
solar maximum
Solar maximum is the regular period of greatest solar activity during the Sun's 11-year solar cycle. During solar maximum, large numbers of sunspots appear, and the solar irradiance output grows by about 0.07%. On average, the solar cycle t ...
. The average latitude of sunspots then continues to drift lower, down to about 7° and then while the old sunspot cycle fades, sunspots of the new cycle start appearing at high latitudes.
See also
*
Solar variation
*
Wolf number
*
Joy's law (astronomy)
In astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objec ...
References
Solar phenomena
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