As the sun sets and dusk envelops the Highland Lakes on Monday, Dec. 21, cast your eyes to the southwest, low on the horizon, to see the Star of Bethlehem.
It’s not actually a star but an astronomical event involving Jupiter and Saturn called a “great conjunction.”
“It occurs every 20 years,” said the Rev. Harold Vanicek of St. Peter’s Lutheran Church of Marble Falls. “But this is the closest (the planets have) been in about 300 years. It’s the first time in about 800 years it has been visible to Earth.”
What is basically happening, Vanicek explained, is that Jupiter is “catching up” to Saturn on their trips around the sun. The two planets travel at different speeds: It takes Jupiter 12 years to circle the sun and Saturn 30 years. Every 20 years, Jupiter and Saturn appear to meet up in the sky as their orbits align.
On Monday, the two planets will appear about a tenth of a degree apart in the early night sky, almost looking as one. The last time the two planets were this close was 1623, but due to astronomical conditions, it wasn’t visible from Earth.
The last time their great conjunction was this close AND visible to Earth was 1226.
In reality, Vanicek said, the two planets are about 200 million miles apart. During the conjunction, they line up with Earth in such a way that they appear to be together.
The pastor does not view faith and science as incompatible pursuits. He studied engineering before attending the seminary, and science remains a large part of his life. During a 2018 sabbatical, Vanicek visited the University of Chicago planetarium and traveled to Europe, where he spent time with Brother Guy Consolmagno, the director of the Vatican Observatory.
The Dec. 21 great conjunction (it’s “great” because it involves two of the largest planets) is also being called the Star of Bethlehem, or Christmas Star, in reference to the star that drew the wisemen to Jesus more than 2,000 years ago. While the great conjunction falls on the Winter Solstice, the longest period of night in the Northern Hemisphere, it’s unlikely this was the “star” the magi spotted in the Middle Eastern night sky.
“Two thousand years ago, what were they following? Nobody knows for sure,” Vanicek said. “There is speculation it may have been Venus and Jupiter, which were in conjunction around 2 B.C.”
It’s OK to embrace the mystery of it all, he said.
Vanicek pointed out that the magi studied the stars and natural world as part of God’s creation, not something separate from it.
“At those times, there was no separation of natural and supernatural, (they were) part of the same,” he said.
To observe the Christmas Star on Dec. 21, Vanicek said look to the southwest and close to the horizon not long after sunset. Jupiter will be the brightest of the two, and it and Saturn will appear as almost one “star.” They’ll likely be the brightest thing in that part of the sky. And while stars “twinkle,” the conjunction of Jupiter and Saturn will steadily glow.
You won’t need a telescope, Vanicek said. You’ll be able to see the conjunction with a pair of binoculars or even just your eyes, weather permitting.
A good tip is to locate the two planets beforehand on Dec. 18-20.
“I would invite people to go out and watch it now,” Vanicek said.
There are phone and tablet apps that can help you locate the two planets. He recommends Star Walk 2.
“The next time (Jupiter and Saturn will) be this close is 2080, and it’s fitting that this one happens on the longest night of the year,” he said. “So, I wouldn’t miss it.”
Vanicek pointed out that during the season of Advent, the Christian preparation for Christ’s birth and return, reflection is important. That can be as simple as stepping outside and gazing up in wonder at God’s creation.
“Maybe just take a few minutes to pause and reflect,” he said. “I think if we need hope this time of year, all we have to do is go outside and look up.