If the earth does not have an atmosphere, the moon will always be visible. So why can you see it only during the day? The
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The moon's appearance in the night sky has fascinated people for thousands of years. But why sometimes the moon is visible during the day?
Sometimes the reason why we see the moon during the day is the same as when we see the moon at night - it reflects the light of the sun - its distance from the earth makes it brighter than the sky during the day or at night. In addition to the sun, the moon is the brightest celestial object we can see.
But the moon is not always visible during the day. This is due to the orbital periods of Earth's atmosphere and our natural satellites. If our planet had no atmosphere, we could see the moon from Earth all the time. Meanwhile, the moon's phase means that when it moves between the earth and the sun - for example during the crescent - the light side is facing us, while the dark side of the moon faces the earth, which makes it essentially invisible to astronomical observers on the earth.
In broad daylight
The gas particles in our atmosphere - mainly nitrogen and oxygen - scatter light with short wavelengths, such as blue light and purple light. This scattering, which involves absorbing and re-emitting light from different directions, gives the Earth a blue sky.
In order to be seen during the day, the moon must overcome the scattered light from the sun. For two or three days around the new moon, observers on Earth cannot see it because its position in the sky means that the sun's scattered light will shine the moon brighter. But, as is usually the case, the relative distance between the moon and the Earth (average 238,900 miles, or 384,400 kilometers) means that the light it reflects seems to us brighter than those farther objects that emit or reflect light, such as stars or other planets.
Illustrations of different moon phases
The brightness of stars visible from the earth is several trillionths lower than that of the sun and one millionths lower than that of the moon. In our sky, the scattered light from the sun is very bright, and it often conceals the starlight during the day, but it is not always the reflected light of the moon.
Astronomers use surface brightness as a way to quantify the apparent brightness of objects in the sky, such as galaxies or nebula, by measuring the amount of light they emit in a certain area of the night sky, as observed from Earth. Since the moon is closer to Earth than the stars, it has a brighter surface than the sky, which means we can easily see it glowing during the day.
However, the visibility of the moon during the day is also affected by other factors, including the season, the current phase of the moon and the clarity of the sky on a certain day.
On average, there are 25 days a month when the moon can be seen during the day. The other five days occur around the new moon and the full moon. As it approaches the new moon, it is too close to the sun to be invisible. When it approaches the full moon, it can only be seen at night, as the moon rises at sunset and sets at sunrise. For a period of time, the only day it did not appear in the sky with the sun was the full moon. That day, the sun goes down, and then the moon rises, and then the other way around, so it's the only day, it's not there at the same time.
The moon has 12 hours a day on the horizon, but its appearance may not always be consistent with the time of day. For example, in winter, when the daylight is shorter in mid-latitude areas, the moon will be visible less during the day.
The best time to see the moon during the day is in the first quarter (a week after the new moon) and in the third quarter (a week after the full moon). In the first quarter, in the afternoon, we can see our natural satellites rising in the eastern sky. In the third quarter, it will be visible in the morning, in the western sky. The moon phase is the longest time the sun and the moon appear in the sky, with an average of 5 to 6 hours a day.
Another phenomenon that affects when the moon will be visible is the light of the earth. During the Crescent period, when the moon is close to the angle of the sun, you can actually see the dark part of the moon, which you shouldn't see because there is light with illuminated light. The dark part of the moon is reflected by reflected light from the earth.The best time to observe this phenomenon is the crescent period, three or four days after the crescent moon.
