Star of Bethlehem.

Star of the East.

Christ’s Star.

It’s been called all those things. But experts still can’t fully explain the three wise men’s guide to Bethlehem.

“There’s no clear-cut scientific explanation,” said Barbara Anthony-Twarog, professor in physics and astronomy at Kansas University. “The one I remember is that it was possibly a conjunction of several planets that had astrological significance. That would explain why certain people took notice of it and others didn’t.”

The Bible relates an out-of-the-ordinary astronomical event that led the Magi to the newborn Jesus.

Matthew’s Gospel account, however, doesn’t explain the origin of the phenomenon or make any reference of others observing it.

Given the Bible’s lack of scientific proof, some, like the Rev. Charles Polifka, a pastor at St. John the Evangelist Church in Lawrence, believe the star could be completely symbolic.

“The whole story of the Magi is really given to us as a story to help us understand that Christ was revealed — that the light of Jesus attracted people from all over the world to Him,” Polifka said.

But Balthasar, Gaspar and Melchior surely had to follow something to Bethlehem — there were no maps available to show them the way, no global-positioning satellites.

There are many factors that contribute to the puzzle of what it was, including the uncertainty in the actual date of Christ’s birth and the terminology used to describe celestial events during the star’s appearance 20 centuries ago.

One widely accepted theory is that of a planetary conjunction — the appearance of two or more planets merging in the night sky. According to astrological computers, those planets could have been Jupiter and Venus sometime around 2 B.C. But planetary conjunctions don’t happen every day, Anthony-Twarog said.

“The last ones that have been noticed in the galaxy were 400 years ago, so they are very rare,” she said.

And plenty of people would have seen it.

“If it’s an astronomical event, it’s kind of hard to be that localized unless it lasts for an extremely short duration and the weather is bad everywhere else,” she said. “Any astronomical event is going to be seen over a very broad region.”

If anyone saw it besides the three wise men, though, they didn’t take the time to make record of it. Astronomers from the Chinese imperialist court and Herod’s in Bethlehem recorded nothing about an unusual occurrence.

Still the lack of scientific evidence surrounding the Star of Bethlehem hasn’t dissuaded centuries of Christians.

“My faith doesn’t depend on whether or not there was some kind of an incredibly bright star,” Polifka said. “I have faith because of the fact that Jesus was revealed to the world and people saw that He was the light of the world.”

Similarly, without proof, scientists can’t rule out chance as a possible sign the star was the first Christmas miracle.

“Signs and wonders don’t usually come with bar codes and labels,” Anthony-Twarog said, “and yes, this was a sign.”