👉 In astronomy, a hydroperiod is an astronomical period during which the Earth orbits its Sun. This period is approximately 395 million years long and marks the end of the last Ice Age in the Pleistocene epoch. The hydroperiods are named after their length, with the longest being called the "Great Hydroperiod" (395 million years) and the shortest being called the "Little Hydroperiod" (150 million years).
