An Inconstant Star

  • Claudio Vita-FinziEmail author


Stars have long been classified on the basis of their brightness; variability was a secondary consideration but eventually proved an important clue to stellar dynamics as well as a means of classification. The Sun’s ~11-year activity cycle, identified mainly from sunspots and other surface features, is superimposed on both longer and shorter periodicities which are manifested in luminosity and internal processes to different degrees. Solar observation thus makes increasing demands on the versatility and sensitivity of observatories, observers and their archives, and rules out an all-purpose definition of the present-day Sun.


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© Springer Nature Switzerland AG 2018

Authors and Affiliations

  1. 1.Department of Earth SciencesNatural History MuseumLondonUK

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