solar minimum
Quick Summary
A solar minimum is a period of reduced sunspot activity. The Sun experiences an approximately 11-year solar cycle where the number and size of sunspots fluctuate. During a solar minimum, this activity is significantly lower than average.
Historically, two notable periods of reduced solar activity are the Maunder minimum (1645ā1715) and the Dalton minimum (c. 1790ā1830). These periods coincided with cooler global temperatures, though the exact mechanism by which solar activity influences Earth's climate remains unknown. While the 11-year cycle continues during these minima, the peak sunspot numbers are much lower.
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space weatherSpace weather phenomenaā¦a several-year period, called the solar minimum, when the Sunās activity can be extremely low. The solar minimum that began in approximately 2007 and reached its lowest point in December 2008 was the deepest minimum in at least a century. The next solar maximum is expected to begin in 2013.
Read Moreā¦a several-year period, called the solar minimum, when the Sunās activity can be extremely low. The solar minimum that began in approximately 2007 and reached its lowest point in December 2008 was the deepest minimum in at least a century. The next solar maximum is expected to begin in 2013.
Read More- space weatherAtmospheric satellite drag
Between solar minimum and solar maximum, the temperature of the thermosphere roughly doubles. The upper atmosphere extends farther during solar maximum, and its density at any given altitude increases. In general, a satellite must have an altitude of at least 200 km (120 miles); otherwise, theā¦
Read MoreBetween solar minimum and solar maximum, the temperature of the thermosphere roughly doubles. The upper atmosphere extends farther during solar maximum, and its density at any given altitude increases. In general, a satellite must have an altitude of at least 200 km (120 miles); otherwise, theā¦
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