Lunar Eclipse Not a Total Wash-Out

Behind the clouds and piercing raindrops, tonight's sky will become even darker due to a total lunar eclipse.

Expected to occur between approximately 11:30 p.m. and 2 a.m. PST, tonight's eclipse coincides with the winter solstice. The last total lunar eclipse visible from California was on Feb. 21, 2008.

A lunar eclipse is the result of the Earth, sun, and moon being in direct alignment, with the Earth positioned between the sun and moon, casting its shadow across the moon.

Lunar eclipses occur about two to four times per year, said Trina Ray, a lunar scientist at . Because the moon's orbit around Earth is tipped by about five degrees, the Moon spends much of its orbit either above or below the plane of the Earth's orbit so the shadow of the Earth falls not on the moon, but above it or below it.

Sadly, with all the rain and cloudy skies, the naked eye will not be able to notice the lunar eclipse, she said.

"If the clouds are anything like [they were] earlier, then I doubt you'll even be able to tell if there is a moon above the clouds.  But it could clear–fingers crossed!'' Ray said.   

Jane Houston Jones, via a Jet Propulsion Laboratory video, explains that a "total eclipse, when the moon is fully in the Earth's shadow, takes a little over an hour."  The Earth's "shadow crosses the moon and the moon darkens." The moon will appear "gray, brown, shades of red or orange, depsnding on how much dust is in the atmosphere," Houston said.

Unlike a solar eclipse, a lunar eclipse can be viewed from any where in the hemisphere where night is in effect, scientists said. 

For earthlings who may not be able to see the sky tonight, such as those of us here in the rainy foothills, NASA will be providing a live video feed of the eclipse on its website, beginning at 3 p.m. PST. NASA's camera is located at the Marshall Space Flight Center in Huntsville, AL.

And what about those pink and red colors that occur during an eclipse? 

Ray said the Earth's atmosphere filters out blue light (the same effect that creates sunsets) and bends the surviving (red) sunlight into its shadow, where it hits the moon.

JPL invites amateur astronomers and enthusiasts from all parts of the hemisphere to join in a live text campaign. Participants will share what they see, even if it's only clouds, and be directed to webcams and images from other participants so that no one is left out of the spectacle.  

While NASA lists June 15, 2011, as the date of the next total lunar eclipse, viewers who live in North America will have to wait until Dec. 10, 2011, to catch sight of one.