A composite picture shows the stages of an August 2007 lunar eclipse before, during, and after totality-when the full moon is completely blocked from direct sunlight. Totality for the December 10, 2011, lunar eclipse will start at 6:05 a.m. PT and last until 6:57 a.m. PT. (See pictures from the previous total lunar eclipse in June.)
Rather than going completely dark, the moon takes on a deep reddish hue during a total lunar eclipse.
"As the entire moon passes through the Earth's shadow cast by the sun in space, sunlight scattering off our planet's dusty atmosphere and subsequently reflecting off the surface of the moon will make it appear to change color," said Raminder Singh Samra, an astronomer at the H.R. MacMillan Space Centre in Vancouver, Canada.
Expect to see the lunar disk go from dark gray during the partial phase to reddish orange during totality, he said.