Free and printable lunar eclipse diagrams are available for you in high resolution! When you are learning about lunar eclipse, you also learn how it happens. A lunar eclipse can occur only at full moon. Lunar eclipses occur when Earth’s shadow blocks the sun’s light, which otherwise reflects off the moon. There are three types — total, partial and penumbral — with the most dramatic being a total lunar eclipse, in which Earth’s shadow completely covers the moon. Take a look at the first diagram below.
The diagram above is the total eclipse. Because the moon’s orbit around Earth lies in a slightly different plane than Earth’s orbit around the sun, perfect alignment for an eclipse doesn’t occur at every full moon. A total lunar eclipse develops over time, typically a couple hours for the whole event. A total lunar eclipse can happen only when the sun, Earth and moon are perfectly lined up — anything less than perfection creates a partial lunar eclipse or no eclipse at all. You can see the process in the following lunar eclipse diagrams below.
Look at the above diagram then imagine this; Earth casts two shadows that fall on the moon during a lunar eclipse: The umbra is a full, dark shadow. The penumbra is a partial outer shadow. The moon passes through these shadows in stages. The initial and final stages — when the moon is in the penumbral shadow — are not so noticeable, so the best part of an eclipse is during the middle of the event, when the moon is in the umbral shadow. (source)
The three types: (1) Total lunar eclipse: Earth’s full (umbral) shadow falls on the moon. (2) Partial lunar eclipse: Some eclipses are only partial. (3) Penumbral lunar eclipse: This is the least interesting type of eclipse, because the moon is in Earth’s faint outer (penumbral) shadow. All diagrams posted above are free to be downloaded.