Hale cycle
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Hale cycle
[′hāl ‚sī·kəl] (astronomy)
The variation of the sun's magnetic field over a period of approximately 22 years, during which the field reverses and is restored to its original polarity; one such cycle comprises two successive sunspot cycles.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.