Today (15th) is the 15th Lantern Festival of the first month of the Year of the Tiger. The fullest moon before and after the Lantern Festival this year is not on the fifteenth day of the first month, nor on the sixteenth day of the first month, but on the seventeenth day of the first month. Astronomical forecasts show that the fullest moment of the moon will appear at 0:56 Beijing time on February 17.
The reporter learned from the Beijing Planetarium that the fullest moon of the first month of the Year of the Tiger will appear at 0:56 Beijing time on February 17. The reason for this phenomenon is due to the cyclical changes in the phases of the moon. This cycle is also called: synodic cycle. On the first day of the lunar calendar, the side of the moon illuminated by the sun is directly opposite to the earth, which is called "new moon", also known as "Shuo". Around the fifteenth day of the lunar calendar, the side of the moon illuminated by the sun is completely facing the earth, and we can see a round moon, which is called "full moon", also called "looking". From "Shuo" to "Wang", and then from "Wang" to "Shuo" is a synodic cycle, which is about 29.5 days.
Experts said that "Shuo" is fixed on the first day of the first lunar month, while the fullest moon "Wang" is most possible in the sixteenth lunar calendar, followed by the fifteenth lunar calendar, which will appear at the earliest on the night of the fourteenth lunar calendar, and the most at the latest appear in the morning of the seventeenth lunar calendar.
Kou Wen, senior engineer of Beijing Planetarium: In the 100 years of the 21st century, there are more than 1,000 full moons, the most of which is the sixteenth lunar calendar, and there are 188 months in the seventeenth round, so there are still more, but the fourteenth round is very rare, just single digits.
According to reports, the last appearance of "fifteen moons and seventeen circles" like this time was on February 26, 2013, and the next time will appear on March 1, 2029.
Source: CCTV News
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