Gift in the Christmas Sky: a Biblically Bright Venus : Astronomy: Tonight after sunset, the planet will be ablaze near the crescent moon, as if a beacon for wise men. It happens about every 25 yules.

The moon and the planet Venus are giving North America a Christmas card this holiday, conjuring up the biblical story of how a bright object in the sky led three wise men to the infant Jesus.

If the sky is clear, Venus--in its three-quarter phase--should be visible Christmas night just below the 2-day-old crescent moon for about one to 1 1/2 hours after sunset, a repeat of Christmas Eve.

“It’s going to kind of look like the kind of thing you have seen on Christmas cards for the past 100 years,” said Jack Horkheimer, executive director of the Miami Planetarium. “This is one of those wonderful events that, even if you are in a brilliantly lit-up city, like downtown Los Angeles or New York, it will be visible.”

Venus, currently about 26 million miles away, is so bright because it is covered with white, reflective clouds. The moon is 225,000 miles away.

The close juxtaposition of the two near Christmas occurs about every 25 years, Horkheimer said. The last time it happened on Christmas Eve and Christmas night was 1965, he said.

“Whenever Venus appears at the time of Christmas, it always causes a lot of conversation,” Horkheimer said. “When it appears with the moon crescent, planetariums’ phones around the country will ring off the hook.”

The conjunction of the two has been portrayed in cave drawings and on ancient pottery.

“It’s the kind of thing that a caveman would walk out and see this magnificence in the sky and couldn’t help but wonder,” he said.

*

So what was the Christmas star that the wise men used as a beacon to guide them to Bethlehem?

“One of the latest theories is that it was a meeting or blending of the light of Venus with the planet of Jupiter because they were so close together,” Horkheimer said.