The Stellar Dynamo; August 1996; Scientific American Magazine; by Nesme-Ribes, Baliunas, Sokoloff; 7 Page(s)
In 1801, musing on the vagaries of English weather, the astronomer William Herschel observed that the price of wheat correlated with the disappearance of sunspots. But the pattern soon vanished, joining what scientists at large took to be the mythology connecting earthly events with solar ones. That the sun¿s brightness might possibly vary, and thereby affect the earth¿s weather, remained speculative.
Thus, in the mid-1980s, when three solar satellites--Solar Maximum Mission, Nimbus 7 and Earth Radiation Budget--reported that the sun¿s radiance was declining, astronomers assumed that all three instruments were failing. But the readings then perked up in unison, an occurrence that could not be attributed to chance. The sun was cooling off and heating up; furthermore, the variation was connected with the number of spots on its face.