Why the Lunar New Year isn’t really a lunar new year
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DURANGO, Colo. — Lunar New Year is the most important holiday for approximately 2 billion people in Asian communities worldwide.
With a growing Asian population, Colorado became the second state in the U.S. to recognize Lunar New Year as an official holiday in 2024. Organized celebrations are held in Denver, Parker, and Colorado Springs.
But when is the Lunar New Year?
In 2025, Lunar New Year takes place on Jan. 29, marking the beginning of the Year of the Snake. In 2026, it will be Feb. 17 and in 2027, it will be Feb. 6. The date usually falls between late January and late February.
Contrary to its name, Lunar New Year doesn’t follow a lunar calendar. Instead, it follows the Chinese calendar, which is a lunisolar calendar.
Video: Ziyi Xu, Rocky Mountain PBS
Three Types of Calendars
There are three calendar systems used on Earth: solar, lunar, and lunisolar.
The most commonly used system — the Gregorian calendar — is a solar calendar. It is based on Earth’s orbit around the Sun. One orbit equals one year, divided into 12 months. The moon’s path is not considered in this calendar.
A lunar calendar, on the other hand, is based purely on the phases of the moon. Each lunar cycle is a month, and 12 cycles make a year. The Islamic calendar is an example of a lunar calendar.
The lunisolar calendar combines the moon’s phases with the Sun’s position. The Chinese, Hindu and Hebrew calendars all use this system, though with different variations.
Throughout history, the Chinese calendar has undergone multiple revisions. The version used today is based on the “Chongzhen Calendar,” officially issued in 1645.
Here’s how it works:
The Lunar Component
Each new moon marks the first day of a month. Since a lunar cycle is about 29.5 days, each month is either 29 or 30 days long.
The Solar Component
As Earth revolves around the Sun, every 15 degrees of orbit is marked, creating 24 divisions called “Jie Qi,” or “24 solar terms.” These terms reflect significant seasonal changes and guide agricultural activities, with names such as “Insects Awaken,” “Corn Forms,” “White Dew,” and “Light Snow.”
Four solar terms are widely recognized: Vernal Equinox, Summer Solstice, Autumnal Equinox, and Winter Solstice.
The Winter Solstice is the most important solar term in the Chinese calendar because a solar year is measured from one Winter Solstice to the next, and it must always stay in November.
However, a challenge arises: a solar year is approximately 365 days, while 12 lunar months total only 354 days. If this 11-day gap wasn’t addressed, the seasons would shift over time, eventually causing November to occur in summer.
The solution? A leap month.
To keep the calendar aligned with the seasons, a leap month is added. Here’s how: Starting from the Winter Solstice, every other solar term is called “Zhong Qi,” or “mid-term.” Between two Winter Solstices, there are 11 mid-terms.
Normally, each month contains a mid-term.
However, when a month lacks one due to the shifting position of the Winter Solstice, it becomes a leap month.
This extra month, typically 29 or 30 days long, is added to the preceding month. For instance, if the extra month comes after March, it would be called “leap March.” And the month following “leap March” would be the new April.
Over a 19-year cycle, seven leap months are added, balancing the extra days and keeping the months aligned with the seasons. Coincidentally, this “7 in 19” rule is also applied in the Hebrew calendar.
Regional Differences
Most countries in the Indo-Pacific region celebrate Lunar New Year on the same day. However, time differences can occasionally lead to variations. For example, the Winter Solstice might fall on the last day of a month in one country but the first day of a new month in another. In rare cases, this results in celebrations a month apart.
In 1985, for instance, China celebrated Lunar New Year on Feb. 20, while Vietnam celebrated on Jan. 21.
A Universal (Earth only) Rule
No matter where you are, the rule is simple: The second month after the Winter Solstice, when you look up and see no moon, it’s Lunar New Year.
Type of story: Explainer
Provides context or background, definition and detail on a specific topic.
Provides context or background, definition and detail on a specific topic.
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