tars can be seen next to the moon as the earth's shadow falls on it during a total lunar eclipse above Beijing December 10, 2011. (Photo : Reuters)
The latest lunar eclipse graces the skies of the Northern hemisphere tonight. It's a penumbral eclipse of the beaver moon. What does that mean?
The moon is at apogee, it's furthest point from the Earth in its monthly revolution. Like the Earth's orbit around the sun, the moon's orbit around the Earth is elliptical, more egg-shaped than a perfect circle.
Its path brings it closer or father away from the Earth as it circles, making it look larger or smaller and brighter or fainter in the sky.
When a full moon coincides with the time when the moon is far away, small and dim, it's called a beaver moon, perhaps so-named because Native American tribes used it as a reminder to set out the last of their beaver traps before the lakes froze over for the winter.
An even more rare event occurs when a beaver moon is eclipsed by the shadow of the Earth as the moon swings around behind the planet and away from the sun, as will happen tonight.
Since the moon is so far away, the Earth's shadow appears blurry on the face of the moon, and doesn't fully hide it, called a penumbral eclipse.
Tonight, most of North America will be able to see 90 percent of the moon cloaked in the faint shadow of the Earth. The East Coast will miss out, because the moon will have already set before the eclipse begins. The best views will be on the West Coast, Alaska and Hawaii, in the early morning hours right before moonset, around 6am PST.
Live Online Streaming
Eager stargazers can watch the eclipse online.