How does the moon phase change occur and what is the moon phase change

It is due to the fact that the earth revolves around the sun, the moon revolves around the earth, and at the same time, the moon revolves around the sun along with the earth. And when the moon is located between the earth and the sun on the first day of each lunar month, facing the earth with a dark side, and haunts the sun almost at the same time, so it cannot be seen on the ground, this is the new moon, also called "Shuo", and the moon continues to rotate forward until the beginning of the lunar calendar.

Seven, eight, the yellow longitude difference is 90 °, the sun sets, the moon is already overhead, in the middle of the night, the moon sets, at this time the moon illuminated by the sun, exactly half of it is seen by you, called "winding". It's time for the lunar calendar.

Ten. 5 and 16, the Moon turns to the other side of the Earth, which is the position 5 in the figure, and the yellow longitude difference is 180°. At this time, the earth is in the middle of the sun and the moon, and the half of the moon illuminated by the sun is exactly facing the earth, and what we see at this time is the full moon, or "hope". Since the moon is exactly opposite the sun, the sun sets in the west, and the moon rises in the east, and when the moon sets, the sun rises again in the east, and a bright moon is visible all night.

After the full moon, the moon rises later and later, and the bright part of the moon is smaller and smaller day by day, and by the twenty-third day of the lunar calendar, that is, the position 7 in the figure, the yellow longitude difference is 270°. Half of the full moon is lost, and the half moon only appears in the eastern half of the sky in the second half of the night, which is the "last string". Towards the end of the month, the Moon will rotate again between the Earth and the Sun, and the waning Moon will rise again in the east shortly before sunrise.

On the first day of the next month, it is a new moon again, and a new cycle begins.

The part of the moon that earthlings see illuminated by the sun changes due to the movement of the moon around the earth.

Categories: Science & Engineering.

Problem description:Please elaborate.,I didn't understand.,It's better to have a picture.,Thank you.,Thank you.。

Analysis: As the moon moves a large distance from west to east in the starry sky every day, its shape is constantly changing, which is the moon phase change, called the moon phase. "People have joys and sorrows, and the moon is cloudy and sunny", and the circle here refers to the "moon phase change":

A different image of the part of the Moon illuminated by daylight as seen from Earth.

Since the moon itself does not emit light, the half of the sphere facing the sun is a bright area, and the other half of the sphere is a dark area. As the position of the Moon changes relative to the Earth and the Sun, the illuminated side of the Moon is sometimes facing the Earth and sometimes facing away from the Earth; Sometimes the part of the moon facing the Earth is larger, sometimes it is smaller, so that different phases of the moon appear.

Whenever the moon orbits between the sun and the earth, and the hemisphere illuminated by the sun is facing away from the earth, people cannot see the moon on the earth, and this day is called the "new moon", also called the "new moon", which is the first day of the lunar calendar.

After the new moon, the moon follows the direction of the earth's rotation, and the bright area gradually turns to the earth, and the moon can be seen on the earth showing a trace of slender silver hooks, appearing in the western sky, bowing its back towards the sunset, this moon phase is called "moth eyebrow moon", which is the beginning of the lunar calendar.

Three, four. Subsequently, the moon moves away from the sun in the sky day by day, at the beginning of the lunar calendar.

On July and August, half of the bright area facing the Earth, one can see the half moon (convex facing west), and this phase of the moon is called the "first quarter moon".

When the Moon moves in the direction of the Earth's back sun, the lunar calendar.

Ten. Five, ten.

On the sixth and seventeenth, the bright areas of the moon are all facing the earth, and we can see a full moon, and this phase of the moon is called the "full moon", also called "hope".

After the full moon, the west side of the bright area begins to deficit, and it is the lunar calendar.

Two. Ten. On the second and twenty-third, you can see the half moon (convex facing east), and this phase of the moon is called the "last quarter moon". During this period, the Moon moves closer to the Sun and rises in the east in the middle of the night.

After another four or five days, the moon turns into a moth-eyebrow-shaped moon bud with its back arched towards the rising sun, and this moon phase is called the "waning moon".

When the Moon moves between the Sun and the Earth again, the Moon returns to the "New Moon".

This is how the phases of the moon change over and over again. If calculated by the cycle of the moon phase change (that is, the entire process of a moon phase change), from the new moon to the next new moon, or from the full moon to the next full moon, it is a "synodic month", with an interval of about a few days, and the length of a month in the Chinese lunar calendar is determined according to the "synodic month".

1. New Moon. The crescent moon is an astronomical phenomenon that refers to the situation that on the first day of the lunar month, when the moon moves between the sun and the earth, the moon faces the earth with the dark side of the black town, and rises and sets with the sun, and the moon cannot be seen on the earth.

2. Waning Moon. After the waning moon, after the full moon, the moon becomes "thin" as the position of the sun and moon gradually approaches. It goes through the gibbous moon, the last quarter and the crescent moon in turn, and finally, returns to the position of the new moon.

In China, it is customary to call the "Moon" in the second half of the month "the waning moon". The waning moon indicates sadness.

3. The first quarter moon.

The moon continues to rotate forward until the beginning of the lunar calendar.

Seven, eight, that is, the position 3 in the figure, the yellow longitude difference is 90 °, the sun sets, the moon is already overhead, in the middle of the night, the moon sets, at this time the moon illuminated by the sun, there is exactly half of the balance for you to see, called the "first quarter moon".

Fourth, the last quarter moon.

Last quarter moon: After the full moon, the moon rises later and later, and the bright part of the moon is smaller and smaller day by day, and on the twenty-third day of the lunar calendar, that is, the position 7 in the figure, the yellow longitude difference is 270°. Half of the full moon is lost, and the half moon only appears in the eastern half of the sky in the second half of the night, which is the "last string".