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What is the 33-year Lunar Cycle & How Does it Work?

Every 33 years the sun and the moon align again. During 33 years, there will be a gap between the solar and lunar calendars because the moon orbits the earth in 27.3 days. Meanwhile, solar months, which are a twelfth of our well-known solar years, last an average of 30 days.

A lunar month lasts 29.5 days. During that time, the moon cycles through its four main phases, which are:

  • New moon
  • First quarter
  • Full moon
  • Last quarter (also known as Third quarter)

Subsequently, a lunar year consists of 12 lunar months. However, a lunar year lasts slightly less than a solar year. Eleven days to be precise. And that’s where the 33-year lunar cycle emerges.

The lunar cycle means a mystery for many people. Furthermore, what event or events occur regarding the moon every 33 years.

The duration of a lunar month and a solar month is different. A solar year, as you already know, is divided into 365 days. Those are the days it takes the earth to orbit the sun. As a result, as days go by, their cycles desynchronize.

The difference in time between a lunar year and a solar year even has its name. Epact is the term used to describe the 11-day difference between both calendars. As a result, we can understand the 33-year cycle in either of the following ways. First, it takes 33 lunar years for the sun and the moon to align for a new occasion. Or second, that they align after 33 successive epacts.

Do special events occur when the 33-year cycle is complete?

As of today, no specific events occur when the lunar and solar calendars synchronize. However, lunar years are still relevant to our day-to-day lives.

For example, the lunar calendar allows calculating the length of the day more precisely. Using the sun, the tilt in axis with that the earth completes a revolution would make days vary in length.

Plus, lunar and solar calendars must synchronize because, otherwise, annual festivities would take place in different seasons over the 33 years. As lunar years are 11 days shorter than the solar calendar, holidays would start coming before the seasons that they are usually tied up.

If using the lunar calendar, a one-month lag between both calendars would appear only after three solar years.