Lunar Eclipse Falls on Winter Solstice for First Time in Centuries

As many as 1.5 billion people worldwide will be able to watch when the Earth's shadow creeps across the moon's surface early Tuesday morning, the first time in hundreds of years that a lunar eclipse will fall on the winter solstice.

With the full moon high in the winter sky, the lunar eclipse will be visible from four continents, with the best views from North America and Central America if weather permits, scientists say.

"It's a really democratic event," Andrew Fraknoi, the chairman of astronomy at Foothill College in Los Altos Hills, told the San Francisco Chronicle, "because you don't need an expensive telescope or any other sophisticated equipment to enjoy the spectacle -- just your eyes or, if you like, a pair of binoculars."

Unlike a solar eclipse, eclipses of the moon can usually be observed anywhere in the hemisphere where the moon is above the horizon.

This particular lunar eclipse also may be seen in totality from northern and western Europe, some of northeast Asia, Hawaii and New Zealand, according to Space.com. In total, some 1.5 billion people may have a chance to see the full eclipse, the website reported.

Total lunar eclipses during winter in the northern hemisphere are fairly common, NASA says. However, a lunar eclipse falling precisely on the date of the solstice is quite rare.

Geoff Chester of the U.S. Naval Observatory inspected a list of eclipses going back 2000 years for NASA.

"Since Year 1, I can only find one previous instance of an eclipse matching the same calendar date as the solstice, and that is 1638 DEC 21," Chester said, according to NASA. "Fortunately we won't have to wait 372 years for the next one ... that will be on 2094 DEC 21."

This year's event will take 3 hours and 38 minutes. The eclipse begins on Tuesday at 1:33 a.m. ET, when the Earth's dark-red shadow will turn up on the edge of the moon, according to NASA. It will take about an hour for the shadow to cover the entire moon. Totality begins at 2:41 a.m. and lasts for 72 minutes.

If you only have time for a quick look, NASA recommends that you take a peek 3:17 a.m. ET. That's when the moon will be fully covered in an amber light.

For more information on how often the December full moon coincides with the solstice, see this explanation of Greenwich mean time and the resulting time zones.

And for a graphic slide show of the lunar eclipse, see the website www.shadowandsubstance.com.