How is the eclipse formed?

Solar eclipse is a phenomenon in nature. When the sun, the earth and the moon are exactly or almost on the same straight line (the earth is between the sun and the moon), the light from the sun to the moon will be partially or completely blocked by the earth, resulting in an eclipse. Eclipses can be divided into three types: partial eclipse, total eclipse and penumbral eclipse.

According to the statistics of observation data, the percentage of lunar eclipse, partial eclipse and total eclipse in the penumbra in each century is about 36.60%, 34.46% and 28.94%. For the earth, the direction difference between the sun and the moon is 180, so the eclipse must occur in Wangwang (around the fifteenth day of the lunar calendar).

It should be noted that the orbits of the sun and the moon in the sky (called ecliptic and ecliptic respectively) are not on the same plane, but have an intersection angle of about 5, so only when the sun and the moon are located near the intersection of ecliptic and ecliptic respectively can they form a straight line and produce an eclipse.

Process:

The process of total lunar eclipse can be divided into five stages: initial loss, eclipse, eclipse, luminescence and last contact.

1, initial loss: the moon just touched the umbra of the earth, marking the beginning of the eclipse.

2. Eclipse: The western edge of the moon is inscribed with the western edge of the Earth's umbra, and the moon just enters the Earth's umbra.

3. What to eat: The center of the moon is closest to the center of the Earth's umbra.

4. Luminescence: The eastern edge of the moon is inscribed with the eastern edge of the Earth's umbra, and the total lunar eclipse phase is over.

5. Last contact: the western edge of the moon is tangent to the eastern edge of the umbra of the earth, and then the whole eclipse process ends.