by Toby Swaford, K-12 Education Coordinator
The moon on the breast of the new-fallen snow
Gave the luster of mid-day to objects below.
– Clement Clarke Moore
Stargazers across North America will witness a rare December solstice / lunar eclipse this evening. The moon will appear to change colors as the Earth’s shadow passes across the lunar surface turning it from gray, to orange, and then, finally, red.
This spectacular display happens when the moon passes behind the earth and enters the earth’s shadow. The earth block’s the sun’s light, which normally shines on the moon and causes it to look white to us, and changing colors of the moon come courtesy of our atmosphere, which will filter the available light.
Tonight’s eclipse is starting at 11:33 p.m. Mountain Time, December 20th (your start time may vary, depending on the local time zone). Some aspects of the event will also be visible to viewers in Western Europe and Asia, but North America is best positioned for viewing. Unlike a solar eclipse, tonight’s event can be seen safely with the naked eye requiring no special equipment (blankets, thermos bottles of hot cocoa, and a lawn chair are optional; but what the heck, you’ve probably got most of that stuff just lying around the house).
What makes tonight’s eclipse even more special is that it’s happening on the winter solstice – the shortest day of the year. A total lunar eclipse coinciding with the winter solstice is fairly unique; the last time the two events coincided was 456 years ago. Luckily, we won’t have to wait that long for another eclipse to come along: the next one is slated for April 15, 2014. Granted, Tax Day isn’t nearly as festive an event as the solstice, and the visibility won’t be nearly as good here in North America, so get out there and enjoy tonight’s show!