"the solar system oscillates with a 60-year cycle due to the jupiter/saturn three-synodic cycle and to a jupiter/saturn beat tidal cycle...
"the solar system oscillates with a 60-year cycle due to the jupiter/saturn three-synodic cycle and to a jupiter/saturn beat tidal cycle...
tibetan calendar:7
tibetan calendar
from the 12th century onwards, we observe the usage of two sixty-year cycles.