Sunspot
noun
1.
one of the relatively dark patches that appear periodically on the surface of the sun and affect terrestrial magnetism and certain other terrestrial phenomena.
noun
1.
any of the dark cool patches, with a diameter of up to several thousand kilometres, that appear on the surface of the sun and last about a week. They occur in approximately 11-year cycles and possess a strong magnetic field
2.
(informal) a sunny holiday resort
3.
(Austral) a small cancerous spot produced by overexposure to the sun
sunspot
(sŭn’spŏt’)
Any of the dark, irregular spots that usually appear in groups on the surface of the Sun (its photosphere), lasting from a few days to several weeks or more. Sunspots appear dark because they are cooler, by up to 1,500°K, than the surrounding photosphere. They are associated with strong magnetic fields and solar magnetic storms moving in a vortex pattern, similar to a tornado on Earth. The number of sunspots waxes and wanes over an 11-year period; at maximum activity there are often increased numbers of solar flares.
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