What Is Moon Face?

The front side of the moon is the hemisphere where the moon is always facing the earth, while the opposite hemisphere is called the back side of the moon. Because the cycle of the moon's revolution around the earth is the same as the cycle of its rotation around its own axis, only one side of the moon can be seen on the earth. This situation is called synchronous rotation or tide lock. The moon is directly illuminated by the sun, and the appearance change around the earth is called the moon phase. The unlit part of the moon can sometimes see hazy images as a result of Earth's reflection. This reflects that the sun's reflection from the earth's surface also illuminates the moon's surface. Because the moon's orbit is a bit elliptical and tilts towards the ecliptic plane, it generates a scale movement, which makes the total surface of the moon that can be observed from the earth reach 59% (but less than half can be seen at any moment).

The front side of the moon is characterized by large dark areas, which are generally considered to be 17th-century astronomers (especially Giovanni Battista Riccioli and Francisco Maria Grimaldi) Named after the sea. Although it was later discovered that there was no water on the moon, the names of these seas continued to be used. The brighter areas are considered land, or more commonly known as highlands.

When mapping the image of the moon to a map, the usual representation is with the north on the top and the west on the left. Astronomers usually reverse the moon map with the south facing up to fit the upside-down image of most telescopes.

When you are on the moon, pay attention to the east-west direction on the moon, usually you don't pay attention. But we are on the earth, and we see the moon in the sky from the earth, so the east and west will be opposite. Therefore, when using coordinates on the moon, you must indicate whether to use geographic (or more specifically, the lunar surface) or astronomical coordinates.

The actual position of the moon in the sky or on the horizon as seen by the observer depends on the geographic latitude of the observer. The following description will consider several typical situations:

• In the North Pole: If the moon can be seen, the closer it is to the North Pole, the closer the moon is to the horizon.

• At the mid-latitudes of the northern hemisphere (North America, Europe, and Asia): When the moon rises from the east, the northeast edge of the moon (sea of danger) faces upward; when it reaches the highest point in the south, the north of the moon is above; and it sinks west At this time, the northwestern edge (sea of rain) is above.

• At the equator: when the moon rises from the east, the north-south axis is parallel to the horizon, and the fertile sea is above; when it sinks westward at about 12.5 hours, the north-south axis is still parallel to the horizon, and the storm ocean is the area that finally sinks below the horizon. Between haunting, when the moon reaches its highest point or zenith, the direction of the lunar coordinates is consistent with the direction on the earth.

• In the mid-latitudes of the southern hemisphere (South America, South Pacific, Australia, South Africa): When the moon rises from the east, the edge of the southeast (Shen Jiuhai) faces upward; when it reaches the highest point, the location is north, and the south faces upward; when When sinking west, the southwestern edge (wet sea) is facing upwards.

• In the Antarctic: The moon behaves similarly to the North Pole, but it faces south