When is the full moon?

The full moon refers to 15 or 16 of each lunar month.

In astronomical phenomena, the moon changes from small to round, which is the full moon, usually on 15 or 16 of each lunar month. The full moon refers to the moment when the difference between the yellow meridian of the moon and the sun reaches 180 degrees (also called full moon), and the moon phase at this time (also called full moon). Two adjacent full moons are always 29.53 days apart.

The most perfect and brightest moment of the moon is when looking. On the first day of the lunar calendar, the moon moves between the earth and the sun, and the illuminated hemisphere of the moon faces away from the earth. We can't see the moon. It is called "new moon" or "new moon". On the fifteenth and sixteenth day of the lunar calendar, the bright side of the moon faces the earth, so we see a round moon, which is called "full moon" or "full moon".

According to the lunar calendar, the new moon is on the first day of each month. But on the first day of the first lunar month, the new moon may occur in the early morning or at night, and each new moon itself has its own length and length. In this way, the "appearance" of the most perfect moment of the moon can appear in the early morning of 15, and at the latest in the morning of 17.

lunar eclipse

Solar eclipse is a special astronomical phenomenon. When the moon went behind the shadow of the earth, the sun was blocked by the earth.

That is to say, at this time, the sun, the earth and the moon are just (or almost) on the same straight line, so the light from the sun to the moon will be blocked by the earth.

As far as the earth is concerned, when the eclipse occurs, the directions of the sun and the moon will be different by 180. It should be noted that the orbits of the sun and the moon in the sky (called ecliptic and ecliptic) are not on the same plane, but have an intersection angle of about 5, so only when the sun and the moon are located near the intersection of the ecliptic and the ecliptic can they be connected into a straight line to produce an eclipse.

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