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Lunar Eclipses

Lunar eclipses occur when the moon passes into the shadow cast by the earth, and they can only happen to a full moon. Sometimes only part of the moon enters the shadow, which causes that part of the moon to turn black and 'disappear'. This is called a partial lunar eclipse. A full lunar eclipse is when the entire moon passes behind the earth into the shadow. When this happens, the moon does not go completely black. Instead, the moon turns orange or red. This light comes from sunlight which passed through the atmosphere and around the Earth. The atmosphere absorbs blue light, which makes the light that strikes the moon appear red to orange. This diagram shows what happens during a lunar eclipse. Although the moon orbits the earth once every 29.5 days, lunar eclipses do not happen monthly. The moon's orbit is actually tipped 5 degrees, so the moon sometimes passes above or below the shadow. This means that lunar eclipses will only happen two to four times a year. Unlike solar eclipses, however, lunar eclipses can be observed safely with the bare eye, and they are visible to the entire night side of the globe. Although not as drastic as solar eclipses, lunar eclipses are still interesting events that are worthwhile to see.

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