The Ancient Egyptian papyrus Cairo 86637 calendar is the oldest preserved historical document of naked eye observations of a variable star, the eclipsing binary Algol — a manifestation of Horus, a god and a king. This calendar contains lucky or unlucky prognoses for each day of one year. Researchers have performed a statistical analysis of the Cairo Calendar mythological texts.
http://www.sciencedaily.com/releases/2015/12/151217151651.htm