December 21, 2010
It's a rare event -- a total eclipse of the moon.
And even rarer is an eclipse that take place during the winter solstice. It meant that the moon was glowing high in the sky during the eclipse overnight.
The 3 1/2 hour spectacle was visible from North and Central America where skies were clear. The totality phase - when the moon was completely immersed in Earth's shadow - lasted 72 minutes.
During a lunar eclipse, the moon passes behind the Earth so that the Earth blocks the sun's rays from striking the moon. This can occur when the moon, the Earth and the sun align so that the Earth is exactly, or very closely, in the middle.
It's the first time in more than three centuries that a total lunar eclipse falls on the winter solstice. The last lunar eclipse on December 21 was in 1638. The next lunar eclipse on December 21 will be in 2094.
You can visit the NASA eclipse website for more information.