STAGE 6

Total eclipse begins

When the last of the Moon enters the umbra, the total eclipse begins. How the Moon will appear during totality is not known.

Some eclipses are such a dark gray-black that the Moon nearly vanishes from view. At other eclipses it can glow a bright orange.

The reason the Moon can be seen at all when totally eclipsed is that sunlight is scattered and refracted around the edge of the Earth by our atmosphere. To an astronaut standing on the Moon during totality, the Sun would be hidden behind a dark Earth outlined by a brilliant red ring consisting of all the world's sunrises and sunsets.

The brightness of this ring around the Earth depends on global weather conditions and the amount of dust suspended in the air. A clear atmosphere on Earth means a bright lunar eclipse. If a major volcanic eruption has injected particles into the stratosphere during the previous couple of years, the eclipse is very dark.

But, as of this writing, no such eruption has happened since our last total lunar eclipse in 2001, so the betting is that this eclipse will be bright.

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