Sky watch: Full moon for lunar eclipse

Late on the afternoon of Dec. 9, watch as the sun sets behind the northwestern horizon.

On that night, the moon's phase is full, and it does everything at the opposite time our sun does. When the sun sets, the full moon rises; and when the sun rises, the full moon sets.

On the morning of Dec. 10, the moon will be undergoing a total eclipse. All sky watchers throughout North America will see the lunar eclipse -- weather-permitting -- but depending on where you live, you may see only a fraction of the show.

The celestial cover-up begins at 6:33 a.m., when the moon will officially begin its journey into the thin outer shadow of the Earth (the penumbra). Viewers on the East Coast will see the moon setting during this phase, but the eclipse won't be terribly noticeable, especially in the glow of dawn.

Not for another half-hour or so will observers notice the slight darkening of the moon's eastern side. Then, about 6:45 a.m. Central Standard Time, the moon's eastern edge will enter the Earth's dark inner shadow (the umbra). Sky watchers across the Midwest will see the moon set as the Earth's shadow travels across the moon's face.

As the light of dawn advances over the West Coast, the moon will dim in the advancing shadow of our planet until about 6:06 a.m., when the moon will become totally eclipsed. During totality, the moon may take on a strange coppery hue and, for viewers under a clear dark sky, will appear to hang in the deep blue twilight to the west. And around it will shine the brilliant stars of the wintertime sky.

mreclipse.com/

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