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This week 50 years ago

21 November 2007

Sunspot number hits new high

Never in the 200 years in which the dark spots on the sun’s face have been counted and recorded has so much disturbance been seen as at present. The sunspot number, which actually takes into account the size of sunspots as well as their number, reached 244 in September and 263 in October. The previous record was 239 in May 1778, and only twice in this century (May 1947 and November 1946) has the sunspot number exceeded 200.

In recent weeks, more than 20 groups of smallish sunspots have been visible simultaneously on many occasions,…

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