Abortion refers to the moon at dawn, and its source is Xie Lingyun's poem "Tomb of the King of Luling in Nanling": "Abortion glows in Yunyang and sunset in Zhu Fang". You can see the moon during the day, but it is not so obvious at night because of the strong sun. The time when the moon appears is related to the revolution of the earth and the rotation of the earth. It moves eastward about 13 degrees every day on average.
Characteristics of the moon
The moon itself does not shine, but reflects sunlight. There is no atmosphere on the moon, and the temperature difference between day and night is very large; The moon has a layered structure such as shell, mantle and core. The earth and the moon revolve around each other, and the birth of the moon has added many new things to the earth; There will be an eclipse on the moon. The surface of the moon is not a good reflector, and its average albedo is only 9%, and the other 9 1% is absorbed by the moon. ?
There are dark parts and bright parts on the surface of the moon, the bright part is highland, and the dark part is low-lying areas such as plains or basins, which are called the moon land and the moon sea respectively. When early astronomers observed the moon, they thought that the dark area was covered by seawater, so they called it "sea".