sunspot number

noun

Definition of sunspot number

: an arbitrary numerical value that is used to describe the sun's spottedness, is the number of individual spots plus 10 times the number of disturbed regions, and depends upon the instrumental equipment and personal equation of the observer

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sunspot cycle

sunspot number

sunspotted

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Cite this Entry

“Sunspot number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sunspot%20number. Accessed 16 Aug. 2022.

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