Venus has an eight-year rhythm, which formed the subject of the world’s oldest astrological text, a Venus-tablet from Nineveh. It was part of a series called Enuma Anu Enlil, the ‘Book of the Gods of Heaven and Earth’, and was dated to the 17th century BC. It effectively recorded the five synodic periods of Venus, giving a series of ten omens over the eight-year cycle through the pattern of Venus’s appearance and disappearance from view.
To the astronomer Johannes Kepler, the musical interval generated by Venus and Earth was a ‘sixth’, given by dividing a string in the fraction 5/8. He said the relation was a ‘marital’ one and varied between the ‘masculine sixth’ G# - E and the ‘feminine’ one of Gb - E. This ratio of 5 to 8 is the key to the pattern traced by Venus against the stars.
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