SkyTour - Lunar Eclipse

Corvus Crux (Southern Cross)

As you can see from the diagram above, a lunar eclipse takes place when the Earth forms a shadow on the Moon's surface. Since the shadow is actually on the lunar surface, a lunar eclipse – unlike a solar eclipse – can be observed from any place on the Earth where the Sun is above the horizon. If the Moon is in the penumbra of the Earth's shadow, some light reaches the Moon's surface and it might be difficult to even see that an eclipse is taking place. When the Moon is within the shadow's umbra, no light directly reaches the Moon and the eclipse can easily be seen from the Earth. A lunar eclipse only takes place during a full Moon. A lunar eclipse does not occur during every full Moon, because usually the Moon passes above or below the Earth's shadow.

But some light reaches the Moon’s surface even when it’s totally within the umbra, although not directly. Light will pass through and be bent by the Earth’s atmosphere. The Moon’s surface will have a reddish-yellowish appearance. Also, the border of the Earth’s shadow is not sharp but fuzzy.

Unlike with a solar eclipse, no special precautions or equipment is needed to observe a lunar eclipse. Just go aside and look. The whole process takes an hour or two and you can see the Moon’s surface gradually being covered by a reddish haze and then restored to its usual color. Binoculars add to the experience but aren’t essential. My most memorable experience watching a lunar eclipse was while doing guard duty at the courtyard of the Cave of the Patriarchs in Hebron where Abraham, Sarah, Isaac, Rebecca, Jacob and Lear are buried. I was standing with members of the Waqf – the Islamic authority – and although we did not have a common language and were separated by tremendous cultural and political differences, we were able to share the experience.

Link to more information on lunar eclipses

Lunar Eclipses for Beginners - Excellent introduction to lunar eclipses

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