Lunar Eclipse December 2010. Lunar eclipse occurs when the Earth lines up directly between the sun and the moon, blocking the sun’s rays and casting a shadow on the moon. As the moon moves deeper and deeper into the Earth's shadow, the moon changes color before your very eyes, turning from gray to an orange or deep shade of red, NASA explained.
In this Lunar Eclipse on 20-21 December 2010, while it is merely a coincidence that the eclipse falls on the same date as this year's winter solstice for eclipse watchers this means that the moon will appear very high in the night sky, as the solstice marks the time when the Earth's axial tilt is farthest away from the sun. Then the moon takes on this new color because indirect sunlight is still able to pass through Earth's atmosphere and cast a glow on the moon. Earth's atmosphere filters out most of the blue colored light, leaving the red and orange hues that we see during a lunar eclipse. Extra particles in the atmosphere, from say a recent volcanic eruption, will cause the moon to appear a darker shade of red.
It's best chance to study for the real phenomenon of Lunar Eclipse of Astronomy, prepare for stay up late tonight because next time it will happen again in the continental U.S. to see a total lunar eclipse until April 15, 2014, according to NASA.