What Was the Christmas Star?

Christmas is a time for tradition, as well as celebration. For Christians, December 25 is most strongly associated with the birth of Christ, with modern-day nativity scenes marked by the angel Gabriel's arrival, the birth of Christ in a stable, as well as kings and shepherds bearing gifts. But one of the most puzzling aspects of the story has long mystified scholars—the Christmas star, also known as the Star of Bethlehem.

The Biblical Account and the Magi

The story of the Star of Bethlehem only appears in the New Testament's Book of Matthew, while other aspects of the nativity appear in Luke. The gospel of Matthew states a bright star sparkled in the eastern sky when Jesus was born, famously seen by a group of wise men. These biblical "Magi," sometimes called kings, are now a key component of school nativity plays. Dr. Daniel Brown, associate professor in astronomy at Nottingham Trent University, said: "The key information can be drawn from the gospel of Matthew, stating that King Herodes was alive, wise men arrived from the east, they saw a star in the East, they went first to Jerusalem and no one in Judea actually noticed or recorded this."

Scientific Theories and Astronomical Explanations

This has resulted in astronomers over hundreds of years offering several scientific explanations for the Christmas star. Dr. Daniel Brown suggests the so-called celestial phenomenon is likely part Biblical interpretation and part embellishment. He added astronomers have long proposed many different, yet ultimately unsatisfactory, candidates as being responsible for this event. Possible astronomical phenomena include:

• Comets, like Halley's Comet.
• An exploding star known as a supernova observed.
• A close meeting between Jupiter and Saturn happening several times—known as a rare triple conjunction.

However, Brown said: "But these objects all fall short, as they would have been seen by others in Judea." He explained that "They would seemingly move through the sky over the night so not really a good sign to follow. Also, if you are coming from the east and following something in the east, it would surely go west not east. So these objects can't really be an explanation."

The Great Conjunction and New Hypotheses

Renowned 17th-century astronomer Johannes Kepler even proposed an astrological dimension as a solution. A conjunction is said to happen when two astronomical objects pass each other due to their movement along the direction of the stars' daily rotation. Because gas giant Jupiter orbits the Sun every 11.9 years while Saturn's orbit takes 29.5 years, a conjunction between the two—called a "great conjunction" due to its rarity—occurs roughly every 20 years.

As another possibility, astronomer Dr. Michael Molnar, former manager of the physics instructional labs at Rutgers, has convincingly argued the star that led the Magi to Bethlehem was actually the moon eclipsing the planet Jupiter. Brown noted that M Molnar proposed in 1999 that the wise men from the east were indeed looking for such an event.

Comparison of Astronomical Candidates