Evidence of Periodicity in Ancient Egyptian Calendars of Lucky and Unlucky Days

  title={Evidence of Periodicity in Ancient Egyptian Calendars of Lucky and Unlucky Days},
  author={Sebastian Porceddu and Lauri Jetsu and Tapio Markkanen and Jaana Toivari-Viitala},
  journal={Cambridge Archaeological Journal},
  pages={327 - 339}
This article presents an experiment in time series analysis, specifically the Rayleigh Test, applied to the ancient Egyptian calendars of lucky and unlucky days recorded in papyri P. Cairo 86637, P. BM 10474 and P. Sallier IV. The Rayleigh Test is used to determine whether the lucky and unlucky days are distributed randomly within the year, or whether they exhibit periodicity. The results of the analysis show beyond doubt that some of the lucky days were distributed according to a lunar… 
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  • L. Jetsu
  • Geology, Physics
    The Astrophysical Journal
  • 2021
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Calendars, clocks, and astronomy