月相与日期（The moon and the date）.doc

月相与日期（The moon and the date） Since the moon itself does not emit light, the half sphere of the sun toward the sun is bright, while the other half is dark. With the moons position relative to the changes of the earth and the sun, making it illuminated by the sun side sometimes toward Earth, sometimes back to earth; sometimes on the part of the earth to the moon is big, sometimes small, there are different phases of the moon. When the moon to run between the sun and earth, hemisphere illuminated by the sun back to earth, people on the earth can not see the moon, this day is called new moon, also called shuori, this is the eve of the lunar new year. The new moon, the moon is running along the direction of rotation of the earth, the bright region is gradually turning to the earth, you can see a glimmer of slender Yingou like the moon on the earth, in the western sky, back toward the sunset, this month is called Crescent, this is the lunar third, four. Then, the moon in the sky gradually away from the sun, to the lunar seventh, eight, half a light toward the earth, people can see a half moon (convex West) this month, which is called moon. When the moon moves to the back of the earth, i.e., lunar fifteen, sixteen, and seventeen, the moons bright region is all over the earth. We can see a full moon. This month is called the full moon, which is also called hope. After the full moon, bright area west began to deficit, the lunar twenty-two, twenty-three, and can see a half moon (convex East), is called the moon this month. During that time the moon moved closer to the sun and rose in the middle of the night. After four or five days, the moon has become a crescent shaped crescent, back toward the sun, the moon is called january. When the moon runs again between the sun and the earth, the moon returns to its new moon. The moon is such a cycle change. If the phase change cycle (i.e. a phase change of the whole process) to calculate, from the new moon to the next, or from one mon