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Jeudi 14 mai
Sunspots are the sites of strong magnetic fields that inhibit heat transport
by convection. The intricate fine structure of these magnetic fields has only
recently been revealed, by observations from the ground and from space. These observations raise theoretical problems, requiring a revised physical model that can be supported by large-scale computation. The global incidence of sunspots varies with a well-known 11-year cycle but the most recent indications suggest that the amplitude of this cycle is currently declining.