The whirlpools of cooling, erupting gas on the sun, called sunspots, wax and wane in cycles of about eleven years, although some intervals have been as short as eight years, others as long as 16. In 1933 sunspot activity suddenly turned upward after languishing near the bottom of a cycle (TIME, Nov. 13, 1933). Since then sunspots have made much news, growing bigger and more frequent, disrupting transatlantic wireless communication and fostering brilliant displays of the aurora borealis. Astronomers looked forward to a peak of activity in 1938 or 1939.
Since sunspot behavior is...
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