The first and second quarters are different states of the Moon, and they have some differences in terms of the timing, shape, and position of their appearance. Here's how to distinguish between the first and second quarters.
1. Changes in the phases of the moon.
The phases of the moon refer to the different forms that the moon takes as it orbits the earth. The change in the phases of the moon is due to the fact that the part of the moon that is illuminated by the sun is different as seen by people on earth as the moon orbits the earth. There are eight types of moon phases, which are the new moon, the first quarter moon, the full moon, the last quarter moon, the waning moon, the bay moon, the bay moon, and the crescent moon. Among them, the first quarter and the last quarter are the two more common phases of the moon.
2. The difference between the first quarter and the last quarter.
1.The time of appearance is different.
The first quarter moon generally occurs at the beginning of the lunar calendar.
The seventh and eighth days of the lunar month, while the second quarter moon generally occurs on the twentieth day of the lunar calendar.
II. XXIII. Therefore, the first quarter moon occurs a few days earlier than the second quarter moon.
2.The shape is different.
The shape of the first quarter moon is arc-shaped, with its arc facing west, while the sun rises from its right side. The shape of the lower quarter moon is also arc-shaped, but its arc faces east, and the sun rises from its left side. As a result, the first quarter moon appears to be more elongated than the second quarter moon.
3.The location is different.
The first quarter moon generally occurs at noon, in the southern sky, and the sun rises to its right. The last quarter moon usually occurs at midnight in the southern sky, while the sun rises to its left. Therefore, the position of the first quarter is somewhat northerly than that of the second quarter.
3. How to observe the first and second quarters with the naked eye.
The way to observe the first and second quarters with the naked eye is simple, just find an open place and look up at the sky. If you are observing at night, it is best to choose a place where there is no light interference. It should be noted that the observation time should avoid the period when the moonlight is stronger, so as not to affect the observation effect.
4. Precautions.
When observing the first and second quarters, you need to pay attention to the following points: First, choose a time when the weather is clear and the sky is darkSecondly, pay attention to safety when observing and avoid falling or touching surrounding obstacles;Finally, if you want to capture the beauty of the first and last quarters, you can choose to shoot with a telephoto lens.
In conclusion, the way to distinguish between the first and second quarters is simple, just need to understand the differences in the timing, shape, and location of their appearance. At the same time, it is necessary to pay attention to safety and choose the appropriate observation time when observing the first and second quarters of the moon.