This year’s Mid-Autumn Festival, the moon on the fifteenth day will be seventeen full!

This Friday (September 25th)

The Mid-Autumn Festival will be ushered in

This Mid-Autumn Festival, the moon is at its roundest

Appeared at 0:49 a.m. on Sunday (September 27)

It is a rare “fifteenth moon seventeen round”

Why does this happen?

According to experts, the moon’s waxing and waning changes

As the moon orbits the earth

caused by changes in the relative positions of the sun, earth, and moon

The starting point of the moon phase change is “Suo”

The date of the new moon is the first day of each month in the lunar calendar

The moment when the moon phase reaches full moon is called “Wang”

From “Suo” to “Wang” to the next “Suo”

form a complete synodic moon

About 29.53 days on average

Since the moon’s orbit around the earth is an ellipse

Running speed is fast or slow

The time from “Suo” to “Wang” will also change

因此，“Wang” may appear in

The fourteenth, fifteenth, sixteenth or even seventeenth day of the lunar calendar

Among them, sixteen is the most, fifteen times

There is also the saying “the moon on the fifteenth day is sixteen round”

Although this year’s “Wang” occurs on the 17th day of the eighth lunar month,

But on the Mid-Autumn Festival

More than 98% of the illuminated portion of the moon has been illuminated