DID THE ANCIENT EGYPTIANS RECORD THE PERIOD OF THE ECLIPSING BINARY ALGOL-THE RAGING ONE?

Journal Article · Sat Aug 10 00:00:00 EDT 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/773/1/1· OSTI ID:22140310

Jetsu, L.; Porceddu, S.; Lyytinen, J.; Kajatkari, P.; Lehtinen, J.; Markkanen, T. ^[1]

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1. Department of Physics, FI-00014 University of Helsinki, P.O. Box 64 (Finland)

The eclipses in binary stars give precise information of orbital period changes. Goodricke discovered the 2.867 day period in the eclipses of Algol in the year 1783. The irregular orbital period changes of this longest known eclipsing binary continue to puzzle astronomers. The mass transfer between the two members of this binary should cause a long-term increase of the orbital period, but observations over two centuries have not confirmed this effect. Here, we present evidence indicating that the period of Algol was 2.850 days three millennia ago. For religious reasons, the ancient Egyptians have recorded this period into the Cairo Calendar (CC), which describes the repetitive changes of the Raging one. CC may be the oldest preserved historical document of the discovery of a variable star.

• OSTI ID: 22140310
• Journal Information: Astrophysical Journal, Vol. 773, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BINARY STARS
CALENDARS
ECLIPSE
MASS TRANSFER
STAR EVOLUTION
VARIABLE STARS