Why does the lunar eclipse occur?

The moon rises and sets every day as it orbits around the earth, even on the night when there appears to no moon. Like the moon, the earth goes around the sun in circle in the period of twelve month. Sometimes the sun, the moon and the earth are aligned exactly or very close so, with the earth between, a lunar ellipse happens. 

Because the light of the moon is actually the reflection of the one of the sun, when a lunar occurs, the earth blocks the sun’s ray from striking the moon. As a result, the moon begins to dim slowly and then disappear often in about a few minutes.

There are two kinds of lunar ellipses: partial and total. The partial lunar ellipse occurs when the moon travels through the umbra part of the earth. In another words, the moon is incompletely shaded. The total one happens when the earth shadow completely covers the moon, only in the full moon. Many people are surprised that the eclipsed moon is reddish but there is a reason. Some of the sunlight passes through the Earth's atmosphere and is bent around behind the Earth and towards the moon. The shorter wavelength of light is scatter and only red wave reach the moon. Consequently you see that the moon is red. In the ancient time, people prayed and begged for the moon to return to the sky while a ellipse because they believe that the planets are the motion of people lived by.