(AP) - It was your last chance to see a total lunar eclipse for nearly three years.

Wednesday's lunar eclipse will be the last total lunar eclipse until Dec. 20, 2010. Last year there were two.

A total lunar eclipse occurs when the full moon passes into Earth's shadow and is blocked from the sun's rays that normally illuminate it. During an eclipse, the sun, Earth and moon line up, leaving a darkened moon visible to observers on the night side of the planet.

The moon doesn't go black because indirect sunlight still reaches it after passing through the Earth's atmosphere. Since the atmosphere filters out blue light, the indirect light that reaches the moon transforms it into a reddish or orange tinge, depending on how much dust and cloud cover are in the atmosphere at the time.